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Fakes & FraudsGreen Obsidian

11th Oct 2006 11:38 UTCGaetano Sicurella

I have recently seen two auctions on Ebay selling green Obsidian from Lipari Islands next to Sicily. These are the links:

http://cgi.ebay.it/MINERALI-OSSIDIANA-VERDE-ACQUA_W0QQitemZ190039766837QQihZ009QQcategoryZ415QQrdZ1QQcmdZViewItem

http://cgi.ebay.it/ws/eBayISAPI.dll?ViewItem&ih=004&item=140037743722&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1

I am very perplexed. What is your opinion ?

11th Oct 2006 13:50 UTCUwe Kolitsch Manager

Definitely looks like synthetic glass.

11th Oct 2006 15:38 UTCAlan Plante

I'd be interested to hear what our Italian friends at Mindat know about the locality this material is said to come from. I think Uwe is probably right - man-made glass - but it is rather difficult to be sure just from looking at a photo. There is naturally occurring green obsidian, but it is rather rare. I only know of a couple of confirmed localities for it, and they are both in the Western Hemisphere - but that may be a locational bias on my part, being in the Western Hemisphere myself. Like I said, I'd like to hear from the Italian collectors who might know something about the Italian locality referenced for the material.

Alan

11th Oct 2006 15:49 UTCDanny Howard

Hi,

I'm with Uwe on this one. I visited Lipari last year and saw nothing like this. Additionally, I spent over a year curating and researching the Johnston-Lavis Vulcanological and mineralogical collection (housed at Univesity College London).

Johnton-Lavis collected extensively from Lipari as well as the other Aeolian Isles, with over 200 rock specimens... none looked like the green glass in the photo!

Typical Lipari Obsidians are shown in the two attached photos (apologies for the quality), the first a banded obsidian and the second a spherulitic obsidian.

Cheers

Danny

11th Oct 2006 15:53 UTCDanny Howard

sorry, heres the second...

11th Oct 2006 19:00 UTCJustin Zzyzx Expert

All colored obsidian such as this is glass.

I've been around a million and a half methaphysical customers that have brought me specimens to show me. All of which turn out to be slag glass.

See The-Vug.com Fakes and Forgeries section.

Thanks!

12th Oct 2006 01:28 UTCPaul L. Boyer

Actually Justin, the fake obsidian section is missing from The Vug. It is in the list, but no discussion section is present.

12th Oct 2006 03:45 UTCJustin Zzyzx Expert

Damn my wife!

She must have chopped it out. Argh...I've got some updates to do anywho.

Thanks for the note!

Justin

12th Oct 2006 17:28 UTCErik Vercammen

There is green obsidiane in eastern Turkey (got a piece from the geological service), but that material is opaque. I agree this looks like manmade glass.

12th Oct 2006 19:05 UTCAnonymous User

I have sold much of this material in our store. It is all green slag, but I have seen many selling it lately as "obsidian". I even get the "wholesellers" coming by selling it as obsidian. Another old name for it is "Mormon Glass".

It comes in a number of different colors. I have in my store red (dark and light colors), blue (dark and light colors), green, aqua and some pieces are mixed and swirled together. Some is opaque and much is clear.

I did have a quy in here a few months ago with a piece that weighed about 5 tons--he had it on a flat bed-semi truck. I thought it would make a great sign for the store but he wanted 10K for it.

Sorry I don't have the ability to take the pics and post them. SOme of this material is very attractive.

Rick

12th Oct 2006 23:28 UTCGiorgio Bogni

Yes, green obsidian is very nice and easy to sale in a shop for methapysical and esoteric use but...is an absolute fake, is glass from China in tree different color: blu, green and red. Make attention is not a natural glass!!

In Torino mineral show, one dealer make some photo "in action" when, he said, work in a Lipari quarry but this foto is false and make only for sale this glass!

15th Oct 2006 21:25 UTCPaolo Malesci

Lipari obsidian is often an homogenous glass without pomix inclusion, but is black and transparent only in thin sections.

I don't know occurrencies of green obsidian in Lipari from Neolitic to 25 years ago (the last time I have been in Lipari).

16th Oct 2006 03:48 UTCJim Bean 🌟

Cleaning a rockhound friend's garage today, we found a big piece of sea-green glass slag, complete with "lythophysae". A great source for some eBay laughs, I think we had it over $50 in value by adding adjectives to the description.

16th Oct 2006 16:03 UTCJoe Dunleavy

I had a piece of "Green Obsidian" analysed a few years ago when my youngest son was attending Penn State. They said it was Green Obsidian but I knew it was not. You see I found it in a crick many years ago when I was fishing. Beside this crick an old factory had burned down and it's very old green tinged windows had melted in the fire and ended up in the stream bed. Thus it appears as Obsidian but is man made glass that God remade into Obsidian with the fire.

The professor never did a valid check on the material but had his assistant do the identifying. Can it be described as a Polymorph of antigue glass? All the right chemical makeup but not the right lineage for a proper mineral.

Joe D.

17th Oct 2006 18:05 UTCJosep Serrano

We went to Torino´s fair and we saw green obsidiane, and also we bough it. In this kind of material always it exist the doubt of if it´s man made or natural.

In nacked eye it looks, in this obsidian, Cristobalite´s crystals inside, that´s what make to supose it natural, because in the black obsidiane from Lipari also it appears this kind of crystals.

Mr. Giorgio Bogni said that the green obsidiane from the Lipari that we meet in Torino, was false. Mr. Bogni, do you have any argument scientific for to be sure about what we said?

Somebody from the forum knows if it´s possible to fabric the glass with cristobalite crystals inside?

Josep M i Montse.

17th Oct 2006 18:54 UTCGiorgio Bogni

Yes Mr Serrano is possible have crystals inside the glass for incorrect fusion and formation of crystals of nefeline or recrystallization of part of the refractary composed from trydimite and crystobalite. Is not enough, you think if in a natural vulcanic place found green transparent and gemmy obsidiane and never people said nothing??? Crystobalite... and the analysis were is? Who said crystobalite in green obsidian whitout analysis?

In "lapis" 31/4 a special page about obsidian (8) said the blue obsidian is glass, this is my analysis; in second I see a lot of kg of this "green obsidian" directli imported fron China and "one nice day" the same arrive from Lipari!!!!

Sorry for my english, but the "obsidiane" exposed in Torino is not from Lipari but from China (I personally know who sale this material) and the same man who sale this "obsidiane" have sulfur from Vulcano, yes but from bolivian vulcano, no fron Sicilia!!!!

17th Oct 2006 19:05 UTCUwe Kolitsch Manager

Grazi Giorgio per queste informazioni importanti.

19th Oct 2006 20:49 UTCGaetano Sicurella

Thanks all for your comments.

It seems clear that we are concerning about a fake.

I can tell you my experience about it. I went to Lipari Islands that are no far from I live (on the Etna volcano) years ago and I found only regular black Obsidian.

Recently, after seeing this kind of green "obsidian", I asked to my brother going to Lipari for vacation to ask for information to local people (like obsidian sellers for tourist or local guides). When he asked where to find green obsidian he got a reply only once. The answer was: "on the moon".

But the auctions go on....

http://cgi.ebay.it/MINERALI-OSSIDIANA-VERDE-ACQUA_W0QQitemZ190041926623QQihZ009QQcategoryZ415QQrdZ1QQcmdZViewItem

20th Oct 2006 07:05 UTCFerdinando Giovine

I'm with Uwe and all that your sample are glass.

In the Lipari Pomice quarrys there are green obsidian, sed it is very rare and it is opaque with black band. There are also Raimbow obsidian, also rare and also opaque. The banded and the sferulitic obsidian are near the conctact with the pomice and it is possible to find also black-green vitreous pomice. The normal obsidian from Lipari is very black vitreous.

I have in my collection all those obsidians from Lipari.

Ferdinando

23rd Oct 2006 13:39 UTCGiorgio Bogni

I writing to italian e-bayer and he change the name, now is only obsidian... not all, but something!

23rd Oct 2006 15:26 UTCAlan Plante

That's nothing as far as I'm concerned. It is NOT obsidian and should NOT be sold labeled "obsidian"...

(I'm getting closer and closer to selling vials of graphite as "diamond dust" for a fat price per vial! It'd be illegal as hell - fraud - but, hey, if I can get away with it, it must be okay - right?)

:~}

Alan

26th Oct 2006 17:01 UTCGiorgio Bogni

The density of green obsidian from Lipari (the fake) is 2,518, normal and natural obsidian is in a range from 2,3 to 2,42, Lipari obsidian (real) is 2,34!

27th Jan 2007 21:34 UTCKristi Hugs

Justin, you are the vug dude? Oh man, I love you!!!!!!! :)) I have gone to your site many times to get accurate info. In fact, was there just the other day looking at what was written on Green Obsidian :) I have a myths and misinformation page on my site where I also post about fakes and forgeries.

thanks for all you do :)

3rd Apr 2007 04:01 UTCMike Pawlikowski

Believe it or not....I have discovered an area in the wooded gamelands of Central Pa that is green obsidian and some of the pieces must weigh in at about 3-4 pounds! Some of it is milky green with streaks of dark green within and others are solid deep green. I even found a few lavendar pieces......Of course, it needs cleaning and all and I got some poison ivy while scavaging for it...Yuck! Still, it is beautiful and it is exciting as it is said to be in the western states in the U.S. Guess, again! I have carried out over around 300lbs easily from the location and it is funny to be walking on it as the glass fragments tinkle under my feet!

Look for it in the news soon enough! It is quite beautiful and the quality is definitely there! I just need to find someone who creates the jewelry out of it as it is like emeralds if the cut is the same.....The darkness of the stone certainly is infuenced by its density......Some pieces are like tennis balls and vary in shape and texture.....

If there is anyone out there who knows who I can contact about getting it tumbled or cut into jewelry, it would truly be appreciated!!!

Peace and Happiness to you all!

Sincerely,

Mike Pawlikowski

3rd Apr 2007 12:18 UTCAlfredo Petrov Manager

Mike, that's called "slag glass", not obsidian. It may well be beautiful, and you might be able to make nice jewellery out of it, but it's manmade, not a natural rock.

3rd Apr 2007 13:50 UTCJennifer Nemitz

Mike P.

I have a friend in Central PA who is into lapidary and was thinking of working with slag glass. Cutting and polishing PA slag may be a little tricky as it tends to break oddly during cutting, but he has had some success. Email me off board and I can get you in contact with him.

8th Apr 2007 15:57 UTCAnonymous User

Can one tell the difference between green slag and green obsidian by macroscopic characteristics? After I had sent a fellow a piece of gneiss (he wanted to make a knife handle out of it), he sent me a "Green Obsidian" knife--with part of the gneiss as the handle.

http://img.photobucket.com/albums/v190/stormbythesea/SAS/ObsidianKnife1.jpg

http://img.photobucket.com/albums/v190/stormbythesea/SAS/ObsidianKnife2.jpg

8th Apr 2007 16:21 UTCAlan Plante

Hi Storm,

It's *possible* but may be difficult. If the material has obvious bubbles in it, it's man-made slag or culet. Naturally obsidian does not have bubbles (except perhaps at a microscopic level) so far as I know. But glass slag may not always have bubbles in it, or a worked piece may have been cut to avoid including bubbles. So a lack of bubbles is not a good "proof" that the stuff is natural. Maybe - maybe not...

Since green obsidian is rather rare it is a good idea to be wary of anything that is labeled as being this. If someone can not tell you the provenance of a piece, I'd discount it - assume its artificial.

BTW: There is nothing in your photos that would help determine what it is. You would have to take a shot with strong light behind the blade, so that any bubbles would be highlighted.

KOR!

Alan

9th Apr 2007 23:12 UTCChris Mavris Manager

Hi y'all,

green obsidian in Lipari, as far as I know, can be found into multicolored layered obsidian veins.

The picture of the italian guy digging at Lipari (the dealer that was at Bologna Mineral Show and at Turin, too) was definitely modified at computer, but I have to confess that he made to convince me that the stuff was real...at least, for a small lack of time!!

Thank God I do collect only crystallized colored chunks!!

:D

Chris

5th Jun 2007 14:06 UTCwaiakwas

I'm curious now to learn whether the green obsidian ring I purchased from Silver by Sajen (Offerings Jewellry) is actually genuine.?????

5th Jun 2007 14:19 UTCAlan Plante

Hi Waiakwas

If you can post a good photo here ("Identity Help" Forum) maybe we can tell you.

Regards

Alan

5th Jun 2007 15:01 UTCJolyon Ralph Founder

Any transparent or translucent obsidian (except in very, very thin slices) is almost guaranteed to be fake. If it looks like glass then it probably is.

Jolyon

27th Jun 2007 15:33 UTCseald

Hi Anybody who knows

I almost bid on the "15.57 ct INVESTMENT GEM - GREEN ANDARA OBSIDIAN - JAVA"; I won the auction for "21.11 ct AAA BEST EMERALD COLOR HIDDENITE (Kunzite)" $60.99 from this Ebay seller FREAKINGCAT GEM, who claims RAREST COLLECTOR STONES ON EBAY!, Thailand that has gazilion "rarest collector or investment gems" that you have no idea what the heck they are. mostly ugly, some got marvelous color and clarity. Any expert's take? I am including the 4 links for obsidian, hiddenite, ruby and assay button. Do they really worth a whole lot? Can anybody tell whether the ruby's for real, under the treatment of ruby, it says "new treatment" what does that mean? any way, may be some gem collector or expert/gemologists can shred some light to this seller's items.

Assay Button

http://cgi.ebay.com/4-71-ct-VERY-RARE-ASSAY-BUTTON-LOCATION-UNKNOWN_W0QQitemZ180090567806QQihZ008QQcategoryZ282QQcmdZViewItem;

Ruby

http://cgi.ebay.com/3-71-ct-FANTASTIC-JEWELRY-QUALITY-RUBY-TOP-OFFER_W0QQitemZ180127271115QQihZ008QQcategoryZ282QQrdZ1QQcmdZViewItem

Andara green Obsidian

http://cgi.ebay.com/15-57-ct-INVESTMENT-GEM-GREEN-ANDARA-OBSIDIAN-JAVA_W0QQitemZ180132300872QQihZ008QQcategoryZ282QQcmdZViewItem

Green Hiddenite

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=180131062446&sspagename=ADME:B:AAQ:US:1

27th Jun 2007 15:38 UTCDavid Von Bargen Manager

Obviously this guy hasn't a clue what he is talking about on some things. An assay button is a chunk of metal from a fire assay. It will normally be gold and/or silver and not a chunk of facetted glass(?)

27th Jun 2007 16:17 UTCseald

Really, glass? I guess it doesn't worth much. I read some where that the assay button is formed when the metal melt (to test the metal) in the ore and the green round dripping/bubbles that looks like button hence the name. Do know what that mean anyway.

I am all confused about this Ebay auction, first time bidding, didn't kown it's so tricky because all feekbacks are so glorious, mine, found out about the green Obsidian from the seller, then the "AAA rarest hiddenite" from Afriganistan I won turned out is not natural but irradiated and will fade out very quick. got ton's of heat from the seller because I don't really want to buy it now. I am really curious, would a natural ruby get gas bubbles inside? saw a few like that. they look very real though. seems there are so many huge rare stones, s---o--- brilliant from Thailand.

anybody know howcome the link I put it just didn't post?

27th Jun 2007 16:26 UTCDavid Von Bargen Manager

For the links to show, you need to be a registered user of this site.

Usually the assay button is what metal remains after the fire assay. The slag tends to be broken up and wouldn't usually be clear. Ruby can have a lot of inclusions in it and vary all the way from clear to translucent (this would be considered to be of minimal value.)

27th Jun 2007 16:31 UTCJolyon Ralph Founder

I hate to say this again, but if you don't know what something is you shouldn't be bidding on it as an "investment gem". In fact, bidding on stuff sight unseen on ebay like this is about as risky as you can get. Anyone can make something look impressive on a photo.

Jolyon

ps. It's clearly listed on the "hiddenite" page that it is 'treated'. So I'm not sure what justification you would have in not going through with the purchase

27th Jun 2007 17:32 UTCseald

I sure have learned my lesson. Even though haven't lost a dime yet, but all the stress and uncertainty, digging around to find out the truth, torture. totally not worth it.

Don't you think it's downright misleading? What does "treated" mean? How many type of gems are not treated? few, fire opal, paridot, tsavorite... For the rest of the gems, most treated. I am ok with all those standard treatment. The problem is that what kind of treatment, temperory, permanent, standard or nonstandard, accepted treatment or unaccepted. May be you all are gem buying warriors. I never have any jewlry bought online (not from Ebay, other american co. and i have huge jewlry collection although not the top notch one) without being information about color treatment about irridated, color enhance, diffused in the product discription, not like putting oil on emerald, it makes a whole lot difference, esp. in case of Hiddenite, it's even a controversal to call it Hiddenite or call it a gemstone with the irradiation because the color would all go away in a few years even without sunlight or strong light exposed vs. the high end extremely rare naturalemerald color. I wouldn't mind if the color enhancement is permanent, like heated ruby, sapphire, tanzanite, aqua...

any way, a lesson to learn. It is just shocking to me, never in the back of my mind would worry about getting something fake before. Guess even though ebay is american co. in this case, doesn't matter.

27th Jun 2007 17:55 UTCDavid Von Bargen Manager

Some treatments:

http://www.ganoksin.com/borisat/nenam/gems-treatments.htm

http://www.jcrs.com/JCRS_for_consumers/jewelry_information/gem_treatments.htm

ebay doesn't sell the items, that is done by individual sellers, many of whom are not in the US and would not be covered by antifraud laws in the US. The more knowledge you have about a subject, the less likely you are of getting defrauded (but even the most knowledgeable people get taken on occasion).

27th Jun 2007 18:21 UTCseald

oh, well, I'd better keep that in mind. I feel awefully bad for the whole bunch of people bidding for the fake stuff. Is there any way to keep mostly our country fellows posted? We had a friend just got ripped off in the Thailand jewlry shop, but the guy insisted he got a good deal, what can you do? interestingly, I saw people with 5000 reviews in ebay are amount the bidders for those green obsidian and hiddenite

28th Jun 2007 02:07 UTCseald

well, it's an eye opener. I am checking and learning from you folks. unbelieverble, gets my nerve. The seller Freakingcat I have problem with have everything here Modavite, Zincite, Tektite, Green Obsidian except Azeztulite. His modavite has bubbles in one stone i looked. If I fight with them and refused to pay for the item, anybosy knows what's the worst could be? Also, I ran to check on the blink which is from an american seller I totally trust, but then who knows the source didn't fool them. There's no mention where the modavite is coming from. doesn't seem like possible to attach any pic file here no matter how small the picture I shrinked. any way, I also found very few tiny bubbles, and I found not so big water/glue/silican kida sustance and brush strok mark in another ring, not like rock inclusion, may be water. the stone look very dark brownish green from the top with nomal lighting and naked eye, even with lighting + 10x loup, no fire not like those on the ebay pic though. thank god, I haven't found my ruby and emerald got bubbles, but, is bubble a sign of fake/synthetic stone? have to check my other stone though. any modavite expert? thanks a lot

28th Jun 2007 16:55 UTCDon Saathoff Expert

Just read...belatedly...the "assay button" additions. Being an assayer, I gotta throw in my bit. When the crucible is poured, the collecting metal in which the precious metals are soluble (lead) sinks to the bottom of the conical mold. The slag floats above the lead. The lead button is a cone and the slag button is a truncated cone. The color of the slag glass can range from opaque black through many shades and transparancies of brown, yellow, green, violet, etc....all depending upon what base metals are are being fluxed out and how much was in the sample. I've saved a LARGE number of slag buttons simply for their beauty...I'm still convinced that the use of glass is a result of ancient assay and precious metal smelting....evidence of fire assay dates to 2500BC!!

5th Jul 2007 07:03 UTCAymeric Longi

Greetings everyone !

I was in Chitral last week, and one of my friend had in his stock big chunks of what he called "Natural Glass". Origin was Afghanistan, although he couldn't give any precise locality (another friend from Panjsheer knows as well about it, but can't give any ocality). Color is of a very nice slightly blueish green. Full clear with bubbles included.

5th Jul 2007 07:03 UTCAymeric Longi

a closer view

5th Jul 2007 07:18 UTCAymeric Longi

Another piece was of a pale aqua blue color. not as clear as other one, with bubbles inside but also yellowish, black and white inclusions.

5th Jul 2007 07:19 UTCAymeric Longi

5th Jul 2007 07:20 UTCAymeric Longi

closer view

5th Jul 2007 07:20 UTCAymeric Longi

even closer

5th Jul 2007 07:23 UTCAymeric Longi

and last one.

Note : I was going to pick another chunk, clear of light yellowish color, but my friend stopped me, saying it was man-made glass.

Cheers !

Aymeric

5th Jul 2007 08:50 UTCJenna Mast

Aymeric:

I have to admit, I'm skeptical. Of the natural glass I've seen, none of it looked like that.

I have seen a few different types of obsidian, usually opaque, moldavite, green, Libyan desert glass, yellowish, fulgerites, and a chunk I found many years ago that may have been amber...and tritinite but that's not exactly natural.

The glass in your photos looks very similar to the chunks of colored glass that are sometimes sold here in the US for decorating purposes.

5th Jul 2007 09:01 UTCAymeric Longi

I am too eheh... but needs more research to find the origin of this affghan glass. still the seller was making a difference between the "natural" chunks he had andother ones which were man-made.

6th Jul 2007 23:57 UTCseald

I don't know whether it's of interest to anybody. I found some guidelines regarding disclosure as Freakingcat Gems harasses me left and right and eBay gave me pressure to pay even though I reported to them about this seller, which they don't care. they want $ obvious more than anything else. any way, thought somebody else may need to use it as I do, so here's what I found from "Gemstone Enhancement" by Kurt Nassau

FTC (Federal Trade Commission of the United States) guides

On gemstones, paragraph 23.20 (c) states: The following are prohibited: The sale or offering for sale, of any diamond or other gemstone, which has been artificially colored or tinted by coating, irradiating, or heating, or by use of nuclear bombardment, or by any other means, without disclosure of the fact that such gemstone is artificially colored, and disclosure that such artificial coloring or tinting is not permanent, if such is the fact.

I'd think a co., from thailand china or whatever land, should adhere to the regulations of the country/region where their consumers are from, just like the food label

I also found that a lot of those ruby out there for bid, big ones like > 9 carats sold for a few hundred $ look very much like the Dyed "Crackled" Quartz illustrated in the same book. to bad I don't know how to get any pic in.

24th Jul 2007 03:03 UTCaaron`

I just recently came across some green obsidian and it is defenately green obsidian. NOT NO STUPID SLAB GLASS! I found pumice and basalt and black obsidian at the same location so there to all you haters of the green obsidian. And its dark green and not lite green and Im confuse on how it got to the place I found it. I also found big chunks of green pumice. I found iron ore and basalt but all in a location where is should not be. If anyone has a clue let me know I found it all in central florida. This place was covered by a huge lake many years ago.

24th Jul 2007 04:19 UTCPaul L. Boyer

I am a bit puzzled since igneous rock isn't usually found on the surface in Florida. Usually need to go deep to find it.

http://vulcan.wr.usgs.gov/LivingWith/VolcanicPast/Places/volcanic_past_florida.html

24th Jul 2007 11:16 UTCUwe Kolitsch Manager

Sounds like somebody dumped some rocks that had been collected elsewhere.

24th Jul 2007 11:59 UTCFerdinando Giovine

Sorry.

These obsidians are from a wrong locality:

http://www.mindat.org/photo-26265.html

http://www.mindat.org/photo-65897.html

There is not any obsidian in Vulcano Island! They are from Lipari Island!

The exact locality is Canneto (near), Lipari, Lipari Island, Eolie Islands, Messina province, Sicily, Italy

24th Jul 2007 12:31 UTCUwe Kolitsch Manager

Fixed/added.

24th Jul 2007 13:39 UTCFerdinando Giovine

If you like here there are biblyografie on obsidian:

http:// www.peak.org/obsidian/bibliography.html

24th Jul 2007 14:41 UTCAntonio Borrelli Expert

Changed the locality of my sample to more generic Eolie Islands.

It was a gift of a friend who went on holiday to this archipelago and he told me it came from Vulcano. Probably he drank too many beers!

Thanks for pointing out this mistake.

Antonio

24th Jul 2007 16:24 UTCFerdinando Giovine

No Antonio.

Ci sono molti venditori di ossidiana alle Eolie. L'ossidiana proviene TUTTA da Lipari, ma te la spacciano per proveniente da Vulcano se te la vendono a Vulcano, proveniente da Stromboli se te la vendono a Stromboli, ...

Poi non Ã¨ escluso che qualche pezzetto venga buttato prima della partenza, anche se acquistato, e ce chi lo trova nel posto sbagliato...ma non esiste nessuna affioramento ad ossidiana nelle Eolie ad escludendum quello sopra il paese di Canneto a Lipari. Fidati.

24th Jul 2007 16:29 UTCUwe Kolitsch Manager

I have been to both Vulcano and Lipari in the 1980s and can confirm Ferdinando's statement that obsidian is only found on Lipari.

24th Jul 2007 17:08 UTCPasquale Antonazzo

Ferdinando devo contraddirti...

Di recente sono stato all'isola di Vulcano e ho trovato personalmente ossidiana...

La localitÃ Ã¨ esatta..

ciao

Pasquale

24th Jul 2007 17:22 UTCFerdinando giovine

Devi fare assolutamente una pubblicazione! E' una scoperta eccezionale! Sconvolgi tutto quello che si sa sul chimismo delle lave di Vulcano! Ti danno il Nobel!

Hehehe

24th Jul 2007 17:34 UTCPasquale Antonazzo

Se non fosse che ho 14 anni....

24th Jul 2007 18:14 UTCFerdinando Giovine

Here one reference of Lipari's obsidian:

Baldanza, Bartolo. 1953. Quarzo e minerali associati nei blocchi di ossidiane a litofisi dei tufi di Lipari. Stromboli (Assoc. Int. Vulcanologi), 1:13-20

24th Jul 2007 18:41 UTCPasquale Antonazzo

questa l'ho trovata io

24th Jul 2007 19:23 UTCUwe Kolitsch Manager

"Di recente sono stato all'isola di Vulcano e ho trovato

personalmente ossidiana... "

Dove esattamente? In situ?

24th Jul 2007 19:39 UTCPasquale Antonazzo

Sono stato sull'orlo del cratere e mentre salivo ho raccolto qualche sassetto...

24th Jul 2007 22:50 UTCAntonio Borrelli Expert

Ferdinando Giovine Wrote:

-------------------------------------------------------

> No Antonio.

> Ci sono molti venditori di ossidiana alle Eolie.

> L'ossidiana proviene TUTTA da Lipari, ma te la

> spacciano per proveniente da Vulcano se te la

> vendono a Vulcano, proveniente da Stromboli se te

> la vendono a Stromboli, ...

> Poi non Ã¨ escluso che qualche pezzetto venga

> buttato prima della partenza, anche se acquistato,

> e ce chi lo trova nel posto sbagliato

Ho aggiornato nuovamente la foto anche se ora sono piÃ¹ propenso ad eliminarla.

Antonio

26th Jul 2007 10:53 UTCGiorgio Bogni

Ci stiamo scannando sul sesso degli angeli...senza accorgerci di questo:

4th Aug 2007 18:07 UTCGiovanni Fraccaro Expert

Ma è sempre la stessa storia, di un altro topic?

4th Aug 2007 18:19 UTCPasquale Antonazzo

No da qui si è spostata in un altro topic...

Ehhh il tacito consenso...

11th Aug 2007 19:17 UTCKristi Hugs

ok, question.....what about "rainbow obsidian" or black obsidian with green sheen, velvet sheen, gold sheen or purple sheen? Are these true obsidians?

11th Aug 2007 19:21 UTCKarl Volkman Expert

Hi Kristi,

Yes the sheen obsidians are natural. several years ago i listened to an excellent presentation on obsidian from oregon. As it was explained the sheen is caused by microscopic bubbles refacting certain wavelenths of light back out of the specimen. The color is dependent on the size and distribution of the bubbles in the layer.

Karl

11th Aug 2007 21:55 UTCKristi Hugs

Thanks Karl!!

12th Aug 2007 08:11 UTCAnonymous User

I picked up these pieces at Glass Buttes, OR, a few years ago:

People call this Gold Sheen Mahogany Obsidian:

http://img.photobucket.com/albums/v190/stormbythesea/Rock%20Collection/Obsidian--GoldSheen.jpg

I've been told that some knappers likely dropped this at Glass Buttes. Apparently Craig Ratzat owns the Burns Green Obsidian Mine in Burns, OR:

http://img.photobucket.com/albums/v190/stormbythesea/Rock%20Collection/Obsidian--GreenBurns.jpg

15th Aug 2007 02:40 UTCChris Pratt

Earlier in this forum, Alan Plante stated that he only knew of a couple of confirmed locations for green obsidian. Does anyone know where the localities are?

My reason for asking is that the BLM is contesting a mining claim for green obsidian. They are stating that it is a common mineral, found in many places and therefore non locatable under mining laws. I need to gather all the intel that I can before the battle. (I dearly love tilting at windmills)

Thanks

Chris

15th Aug 2007 05:06 UTCAnonymous User

Just to clarify...I've been informed that Craig Ratzat does not own that mine and that it is in Burns, OR.

15th Aug 2007 05:57 UTCChris Pratt

Thanks Storm

You are correct, Craig allowed the claim to lapse. This is the same claim that the BLM is contesting. (I filed shortly after he allowed it to lapse)

I am looking for any other green obsidian locations,

15th Aug 2007 14:00 UTCDavid Von Bargen Manager

Oregon & Pachuca

http://www.davehaskell.com/field2005.html

TENORIO, D., A. Cabral, P. Bosch, M. Jimenez-Reyes, and S. Bulbulian (1998)

Differences in Coloured Obsidians from Sierra de Pachuca, Mexico. Journal of Archaeological Science 25(3):229-234.

http://www.peak.org/obsidian/abstracts_t.html

http://www3.interscience.wiley.com/cgi-bin/abstract/106571792/ABSTRACT?CRETRY=1&SRETRY=0

http://journals.cambridge.org/action/displayAbstract;jsessionid=1160F64DC4F2FC542CE8A58ABB21FB81.tomcat1?fromPage=online&aid=420080

20th Aug 2007 03:28 UTCPaul Stahl

The only locality of know of that definitely does produce high gem grade green obsidian is Sri Lanka. I have seen crystal clear pieces up to the size of a closed man's fist pass gemmological testing. I agree though that you should consider as dubious most green obsidian that is presented as such in an uncontrolled market. As the other guys have said, the real deal is very scarce worldwide. I believe there are also deposits in Indonesia but as I haven't seen any of the material I can't comment on quality.

27th Aug 2007 13:08 UTCJosep Serrano

Hello: We have traveled to Lipari and even Vulcano to see obsidian. In Caneto (Lipari) it has very many and she is black and there is another one with esferulas white that is looked like the Snowflake.In the archaeological museum of Lipari can be seen hundreds of obsidian tools. We asked workers of the obsidian of lipari for the obsidian of green color and they said all to us that not exist that it was glass done by man-made. Nobody in the Island knows to nothing of green obsidian with quality gem. We discarded that obsidian which we bought in the fair of Torino is natural. The material this analyzing itself in the University of Nantes and when we know the result we will publish it. On the other hand we if we found black obsidian in abundance in the island of Vulcano.

27th Aug 2007 14:49 UTCJolyon Ralph Founder

Until I see evidence of gem-quality green obsidian in the field, I find it hard to believe that any of this so-called natural obsidian is anything other than man-made glass. It's not too hard to create something that passes basic gemmological tests. Show us the stuff in the wild and I'll believe it.

Jolyon

14th Dec 2007 14:25 UTCTim Fisher

storm Wrote:

-------------------------------------------------------

> Can one tell the difference between green slag and

> green obsidian by macroscopic characteristics?

> After I had sent a fellow a piece of gneiss (he

> wanted to make a knife handle out of it), he sent

> me a "Green Obsidian" knife--with part of the

> gneiss as the handle.

>

> http://img.photobucket.com/albums/v190/stormbythes

> ea/SAS/ObsidianKnife1.jpg

> http://img.photobucket.com/albums/v190/stormbythes

> ea/SAS/ObsidianKnife2.jpg

This is a rather nice knife of Burns green sheen obsidian from Oregon. The previous reply to this message was incorrect, it is not man-made but a natural green sheen obsidian mined from a claim a few miles north of Burns, OR. Alan: I have pieces of obsidian that I dug myself from Glass Buttes, OR that are packed full of bubbles. The trick is, they are all stretched by the movement of the flow as it cools. So, until someone deliberately fakes obsidian by letting the glass flow slowly as it cools, all man-made glass will betray itself by the presence of spherical bubbles. Natural obsidian, since it is flowing as it cools (if it wasn't flowing it would be rhyolite, not obsidian) ALL has elongated bubbles, both macroscopic (some) and microscopic (all, AFAIK).

14th Dec 2007 14:38 UTCTim Fisher

Paul Stahl Wrote:

-------------------------------------------------------

> The only locality of know of that definitely does

> produce high gem grade green obsidian is Sri

> Lanka. I have seen crystal clear pieces up to the

> size of a closed man's fist pass gemmological

> testing. I agree though that you should consider

> as dubious most green obsidian that is presented

> as such in an uncontrolled market. As the other

> guys have said, the real deal is very scarce

> worldwide. I believe there are also deposits in

> Indonesia but as I haven't seen any of the

> material I can't comment on quality.

You were shown pieces of man-made green glass. Sorry, but it's simply not possible for green obsidian to form naturally. Unless chromium or copper sneaks into a rhyolite flow as a significant trace mineral, which hasn't happened anywhere on this planet yet.

14th Dec 2007 14:40 UTCTim Fisher

Aymeric Longi Wrote:

-------------------------------------------------------

> Greetings everyone !

>

> I was in Chitral last week, and one of my friend

> had in his stock big chunks of what he called

> "Natural Glass". Origin was Afghanistan, although

> he couldn't give any precise locality (another

> friend from Panjsheer knows as well about it, but

> can't give any ocality). Color is of a very nice

> slightly blueish green. Full clear with bubbles

> included.

Every single one of these is clearly green glass. It looks nothing like any natural obsidian. I can even see the spherical bubbles in many of them, and that is a dead giveaway. Natural obsidian NEVER has spherical bubbles, it is simply not possible for an obsidian flow to cool after it has stopped flowing and still be obsidian (it would then be rhyolite).

14th Dec 2007 14:57 UTCTim Fisher

Alan Plante Wrote:

-------------------------------------------------------

> I'd be interested to hear what our Italian friends

> at Mindat know about the locality this material is

> said to come from. I think Uwe is probably right

> - man-made glass - but it is rather difficult to

> be sure just from looking at a photo. There is

> naturally occurring green obsidian, but it is

> rather rare. I only know of a couple of confirmed

> localities for it, and they are both in the

> Western Hemisphere - but that may be a locational

> bias on my part, being in the Western Hemisphere

> myself. Like I said, I'd like to hear from the

> Italian collectors who might know something about

> the Italian locality referenced for the material.

>

> Alan

Alan, please tell us where these locations are. I have never seen natural green obsidian that was not green sheen, or simply greenish black opaque obsidian, and I have been to a few dozen obsidian locations in the western US, and have samples from dozens more in my collection.

14th Dec 2007 15:26 UTCUwe Kolitsch Manager

see

http://www.mindat.org/mesg-5-82418.html

7th Jun 2008 12:27 UTCjeff hitchcock

Here's an interesting piece but it's not obsidian or slag. It has no bubbles present but etchings of somesort that look man made. Interesting piece to say the least. Jeff

7th Jun 2008 13:33 UTCUwe Kolitsch Manager

Typical slag, sorry.

7th Jun 2008 17:45 UTCJeff Hitchcock

Green moldavite is created by impact processes like the specimens found in Libya or in the Czech Republic. It's light green and has been launched by a meteor or asteroid impact. The glass here comes from an impact crater and is not created by volcanism or any other igneous processes but metamorphic changes in host rock(limestone) due to friction during an intense impact. Please note: there is a elongated black tektite located on the far left in the middle. It was spun out of the crater and elongated by gravity while spinning in the atmosphere. The other pieces were left to cool inside the crater.

Cheers,

Jeff Hitchcock

7th Jun 2008 18:51 UTCUwe Kolitsch Manager

Sorry, this doesn't look like an impact glass at all.

29th Jul 2008 20:55 UTCDavid G

My mother-in-law recently passed away and left a large collection of rocks which she and my father-in-law collected 30-40 years ago. we have a fairly large piece of obsidian which is a very dark green, very brilliant green when held in the sunlight. (by "large" I mean about 10 inches across)They collected it at Glass Buttes in Oregon many years ago. In reading all these posts, most indicate you don't believe there is any natural green obsidian. We are not rock specialists and know nothing about the rarity of green obsidian except for what we are reading here. I have no reason to doubt that this was collected at Glass buttes because that is what she told us. So how do we go about getting this piece tested to see if it is one of those very rare pieces of green obsidian? One side of this piece has been cut on their rock saw and it did not crack or shatter. Would glass shatter when cut?? I can send a picture if you are interested in seeing it.

7th Aug 2008 20:37 UTCUwe Kolitsch Manager

Yes, please upload some photo(s).

The locality/area is this one: http://www.mindat.org/loc-22138.html

8th Dec 2010 02:53 UTCgreen obsidian / natural glass

natural glass / obsidian stone

natural glass / obsidian stone

16th Aug 2012 19:52 UTCangiebaumgardner

most of the obsidian ive found is a mossy green color..and it is real..found a vein..i have pounds lol How do i go abt selling it??

17th Aug 2012 00:10 UTCD Mike Reinke

Maybe a rock and mineral shop will buy or consign it, I don't know.... A lady near me put it in the Advertiser, a local ad paper that she had a collection to sell. i went to look, it was mostly chert quartz, and feldspar, one 1" amethyst, an ironstone...Next to nothing, really, but I saw her later, and some healy-fealy lady gave her $45 for some of it...WOW Glad she made out! Scoop up your driveway, and sell it in the Advertiser.

17th Aug 2012 11:02 UTCGuenter Blass

Hi all,

I do not know if there on Lipari it gives green obsidian ( green volcanic glass ), but I'm sure it's in the volcanic Eifel, Germany, both blue and green volcanic glass is.

I've already written about it here in the forum times ago (see also extra Lapis No. 34).

Sorry for my bad english.

Günter

18th Aug 2012 18:42 UTCUwe Kolitsch Manager

NOTE: The blue and green volcanic glass Günter refers to forms as a more or less thin rim on xenoliths in basaltic lava, and is extremely rare.

It has nothing to do with obsidian.

16th Feb 2015 07:48 UTCarlan

Hi sir

My name is arlan from indonesia, I live in buton Island which well known by asphalt mining.

if you can see my stone picture that I attach, I found that obsidian stone and check in 3 gems lab, they said man made glass. Funny thing is, I found this stone in the forrest of minning asphalt using excavator which has no record or history people make glass on the land before.

If someone want to know more and we can share easily, here's my email address: laodemarlan@yahoo.co.id, my Whatsapp number: +6282122440783

16th Feb 2015 08:11 UTCarlan

For green obsidian on my picture

we only found less than 20kg. I only have 1kg, others kg on local people and we dont find it anymore

16th Feb 2015 08:53 UTCarlan

Hi, this another stone what I mention before. we find in natural places, so it could be natural stone. I communicate with lee horowitz which my old customer of chrysopal and if I'm not wrong, he is a well gemologist, he mention this obsidian could be same like italy obdsidian which ever found in small amount in year 1957-1958. I still confused what is this stone... I hope someone can make me give a good information. And one thing, it have a bubble in it so I believe one of a readers will said this is "man made glass", but since we found it in the middle of forrest in asphalt mines and we dig it by excavator in the deep ground, By the history of how we found it, I think it should be a natural, but still unsure. So, please share your opinion for me

16th Feb 2015 14:20 UTCReiner Mielke Expert

"we found it in the middle of forrest in asphalt mines " Volcanic glass is associated with volcanic rock, asphalt is not, it is associated with sedimentary rocks so it is unlikely that you have obsidian. If there was mining activity there was also likely garbage produced which was buried. Although the photo is bad from what I can see it looks like manmade glass to me, possibly melted bottles from a barbage fire.

30th Oct 2019 03:42 UTCAnna Long

This forum is years old at this point but I would like to share that glassy bright green obsidian was found about three years ago in Ethiopia. I have two very large pieces in my possession both with snowflake and one still attached to the feldspar base, and I know about two tons of it in various degrees of darkness has been recovered from the same location. The company I work for ran the entire mining operation so it is 100% true that high quality glassy green obsidian can and does occur naturally.

We are turning some of it into jewelry and it’s turning out so beautifully but I’m concerned no one will believe it’s authenticity unless they are able to see the original specimens.

Anyways, we have had many people come in after seeing our pieces with their own local discoveries (being from Pa there is plenty of slag glass to go around), so it’s been fun explaining to people the difference.

30th Oct 2019 09:01 UTCLuca Baralis Expert

I'm curious about what you mean with "glassy bright green".

Any picture of these pieces?

30th Oct 2019 15:03 UTCPaul Brandes 🌟 Manager

Both of the specimens and in situ photos would be nice.....

30th Oct 2019 15:53 UTCTony Albini

On a related topic, I was shown a beautiful light blue "obsidian" from Mexico. I checked the internet and found this was listed as naturally occurring in basalt in a province of Mexico. The Mexican person who showed me the piece said he saw it in situ on land owned by Native Americans in the area. Has anyone seen material like this?

30th Oct 2019 17:43 UTCKevin Conroy Manager

I've seen green and blue obsidian, always as a schiller effect. The proper term for this type is sheen obsidian or rainbow obsidian. I have never seen or heard about green or blue obsidian that is translucent or gemmy.

30th Oct 2019 18:45 UTCPaul Brandes 🌟 Manager

I have seen green obsidian in situ only once that I would call glassy and not caused by any schiller. I have heard blue exists, but it is very rare.

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