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Identity Helpwhat to do about 'vulcanite'

12th Oct 2017 21:22 UTCDona Leicht

Everyday we get offers of 'fabulous', 'incredible', 'beautiful' specimens - rarely is there something of real value. I find that I have offended those people by having to tell them that their piece is hardly more than garden rock, let alone a collector specimen. The photo shows an example: this person claims this is a naturally occuring vulcanite which measures 9" x 9" - how to break it to them gently?? I hate to just ignore the e-mails. And just WHAT IS THIS piece really???

Thanks for some suggestions.

Dona Leicht

Kristalle

12th Oct 2017 21:50 UTCDona Leicht

-- moved topic --

12th Oct 2017 22:33 UTCPaul De Bondt Manager

Looks like man-made carborundum SiC ( silicium carbide )

Look at the blue hues on the base of the specimen.

I presume the specimen is quite light for it's size.

I hope this helps.

Paul.

12th Oct 2017 22:43 UTCPavel Kartashov Manager

Crystals on the sample are too large and well formed for carborundum. Besides that it is high lustrous and fluorescent in SW UV.

I bet for pyroxene crystals in metalurgical slag.

Photo of the back side of the item would helps.

13th Oct 2017 00:26 UTCKevin Conroy Manager

Dona, I think you can safely say that this isn't vulcanite. Send them the link for the mineral ( https://www.mindat.org/min-4213.html ), and maybe suggest that since there's a question about the identity that you're not interested in it at this point.

13th Oct 2017 09:10 UTCJolyon Ralph Founder

You can tell them it isn’t CuTe enough to be a vulcanite.

13th Oct 2017 09:25 UTCAlfredo Petrov Manager

But if they have a vulcanite realgar, then we all want it.

13th Oct 2017 13:01 UTCJoel Dyer

Nice one, Jolyon :-)

13th Oct 2017 13:16 UTCEd Clopton 🌟 Expert

Dirt or dust could account for the lack of the luster we expect from carborundum--this piece appears to have sat in a dusty place for some time--but more significantly, carborundum crystals tend to be thin tabular, and these look more wedge-shaped. I agree that it's probably not carborundum, but I can't guess beyond that. I don't suppose the owners have any info about locality or provenance . . . .

13th Oct 2017 14:52 UTCSteve Hardinger 🌟 Expert

Dusty hematite?

13th Oct 2017 15:30 UTCReiner Mielke Expert

Pavel,

I have seen many specimens with large well formed carborundum crystals. However they do look wedge shaped unlike carborundum. But it does look like some sort of artificial product

13th Oct 2017 16:05 UTCDonald Lapham 🌟

I agree with the Silicon Carbide (Carborundum) ID. Living near Niagara Falls ON/NY they are plentiful up here. Many folks who worked at the old plants brought home the crystals that formed in gas cavities in the melt. Some specimens and individual crystals could get quite large. A good spray with water and it should return to a very sparkly beautiful piece.

13th Oct 2017 16:37 UTCMark Andrews

Well done Alfredo. I see what you did there :-P

That joke is practically elemental.

13th Oct 2017 16:54 UTCDana Morong

Maybe you could tell them that you only know and deal with minerals that are from Planet Earth.

13th Oct 2017 16:56 UTCBob Harman

If SUPERMAN can be so intimately associated with kryptonite, then perhaps we should ask MR. SPOCK's opinion on VULCANite!

heh heh heh..... CHEERS......BOB

13th Oct 2017 22:43 UTCMark Heintzelman 🌟 Expert

Agree with Donald, I've seen some with fairly large xtls as well. The only example image I have is a poor one, but this specimen is nearly 4 inches across.

13th Oct 2017 23:12 UTCJolyon Ralph Founder

No need to debate. Look at the photo carefully.

It 100% is a silicon carbide with flat hexagonal plates.

Ugly one though....

14th Oct 2017 00:36 UTCPavel Kartashov Manager

Yes, look at the photo carefully and you'll see that this isn't carborund. :)

I don't see any reaction of topicstarter. In such situation indeed any debates are excessive.

14th Oct 2017 02:03 UTCReiner Mielke Expert

Either way it is manmade and not worth worrying about.

18th Oct 2017 11:02 UTCUwe Kolitsch Manager

Possibly dull oxidised siderite?

Ask these people to check the hardness.

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