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Australian Selenite question

Posted by Jerry  
Jerry
Australian Selenite question
September 21, 2006 11:17AM
Howdy! For many years now I've had a great example of an Australian Selenite crystal cluster in my collection. I wonder if any Down Under folks here can educate me as to where these are mined and how they are formed? I'm talking about a thin plate with numerous crystals sticking out top and bottom, so that it looks like it formed as a mineral layer on standing water.

I've always thought it was some sort of cave formation, but info I've found on the internet seems to indicate these are from actual lakes. Given how many of them are being sold on ebay, it doesn't seem to be cave formations.

Any help?
Re: Australian Selenite question
September 21, 2006 11:54AM
Jerry, Our Down Under friends will correct this if I'm wrong, but I believe these gypsum specimens are recent growths in the settling ponds created for holding acid mine runoff. Lots of metals (Fe, Cu, etc.) are dissolved in the acid water, hence the bright orange and green colors.
Re: Australian Selenite question
September 21, 2006 11:59AM
We should add that if, as I've been told, these specimens are indeed from acid wastewater holding ponds, then technically they are synthetic crystals and not real minerals (whether or not the growth was intentional or unintentional). But they are pretty nevertheless.
avatar Re: Australian Selenite question
September 21, 2006 04:30PM
ca    
The dealers that I spoke to and purchased said minerals from in Tucson and Denver this year, said that it was from a lake bed type deposit and didn't offer up any mention of settling ponds, especially since the orangey brown and green varieties that have shown up at Tucson earlier on this year and at Denver just recently, have color origin questions that their associates posited were possibly from iron salts in the solutions. The one specimen that I got, still had small branches in the material which apparently were part of growth on the edges of the area. The specimens that I got, both had two generations of colour the base being slightly brown amidst clear chisel shaped crystals, and a second layer that was composed of smaller crystals of the brighter colour. [check out Ausrox on this as they were one of the suppliers of Halites and selenites with these colours..]
Jerry
Re: Australian Selenite question
September 22, 2006 12:55AM
That must be some nasty stuff in those runoff ponds. It seems to make sense and explains the unusual formation. I do think that it means people who sell these should make sure to let the buyer know that they are not "natural". But they're cheap enough and have such nice crystals, it's still a nice item to have in my collection.

We still have yet to hear from our friends Down Under. A bloke must need to wear protective rubber outfit and gas mask to get around these lakes.
avatar Re: Australian Selenite question
September 22, 2006 04:16AM
ca    
When I got mine, I was told that they were from a marshy lake area near Mount Gunnerson, at least that was my memory of the locale. I invite the Ausrox/ Crystal Universe people to reply to this for the sake of correcting the misinformation that seems to be flying around about this....
Re: Australian Selenite question
September 22, 2006 12:13PM
Jerry, you certainly would NOT need "to wear protective rubber outfit and gas mask to get around these lakes" /swamps, whatever, even if they are contaminated with mine runoff! I've collected stuff from mine runoff in Bolivia and the U.S.A. The water can be quite acidic, will sting your skin if you have any cuts or abrasions. I wouldn't recommend using the water for drinks, but the pretty specimens are harmless. (Or at least no more dangerous than any other mineral specimens from mines.)
avatar Re: Australian Selenite question
September 22, 2006 05:47PM
Ok...Someone from down under guys. :) No, they are not from run-off ponds. They wouldn't survive long in acid! Rays source is more on the money. We have heaps of Selenite along the Murray River, the main river of of my state South Australia and landlocked briney lakes. It is really just a bedded Gypsum crust with higher salinity than possessed by standard Gypsum crusts. This higher level of salinity is also what allows the formation of specimens of nodular gypsum to occur. It does not always display crystals.

High quality Selenite from the Murray River Region can look like a solid lump of glass and I have seen some amazing specimens with preserved animals and shells inside the specimen. The most notable being a perfect cowrie shell trapped in a block of selenite that looks as fresh as it would have when trapped in the Selenite..even the original colours are still across the shell. I was so stunned by the specimen I forgot to photograph it! Uwe has probably viewed the same specimen at Mannum and may be able to offer more on the subject of Australian Selenite. I have to visit the holder of this specimen this week so I will upload photos of some of his specimens when I return if he approves.

Paul Stahl

ps I can always accesss some good Selenite for trading but specimens with biological matter inside are rare these days as bans on the deposits have been placed due to damage being done by professional fossil hunters and foolhardy amateurs with sledgehammers.
Ian Bruce
Re: Australian Selenite question
September 22, 2006 07:46PM
I originally collected at this locality at Mount Gunson in 1993 and was the first to bring this material to the market. The deposit is in the Pernatty Lagoon just below the Mount Gunson mine. The area is very arid and there is strong evaporite mineral formation resulting in the growth of either halite or gypsum depending on the precipitation cycle....typically the halite came later than the selenite coating it completely. The deposit that produced the said specimens is a flooded copper open pit mine actually in the bed of the Pernatty lagoon which lies just below the current( Or then current) Mount Gunson copper mine. There were extensive heap leach dumps at the mine using sulphuric acid to leach copper from the low grade sulphide ore and there is no doubt that some of the sulphate ions that help form the selenite would have been from 'run off' from the heap leach piles. The green coloration was due to layers of iron sulphates within the growth bands of the selenite crystals.
There is very extensive selenite growth in all the evaporite lakes in this region but as far as I know the green coloration is unique to this location....hope this helps...
PS.It is worth noting that I am very dubious about the coloration of some of the 'green' selenite produced over the last decade.
JerryC
Re: Australian Selenite question
September 23, 2006 01:21AM
Hmm...so they are formed under the right conditions in supersaturated lake or pond water, that might or might not be associated with mine dumps. The water couldn't be fit to drink. That is some definite strange landscape you folks live in, mate!
Re: Australian Selenite question
September 23, 2006 05:53PM
at    
Have added a comment to the locality.
Re: Australian Selenite question
October 12, 2006 07:28AM
i recently found selenite in the simpson desert .not much water around there .with thin sheets lying on top of a black find dust.
JerryC
Re: Australian Selenite question
October 16, 2006 12:56AM
One description I found of these selenite plate specimens is that the plate is a deposit on a mud surface, and then the crystals grow down into the mud or sand and that material must be cleaned off to reveal the selenite crystals. Is this correct?
Re: Australian Selenite question
October 16, 2006 01:10AM
i dont know a lot about it but what you said ,in the desert when it rains the dust would definatly become mud ,when it drys out and the erosion of wind and rain would expose them.
Re: Australian Selenite question
October 23, 2006 11:31AM
Hi Guys,
The selenite or Gypsum is pretty common stuff. I have some pics on my new site at: stwsales.com/agcd.html
Some of the gypsum crystals found in all sorts of large soft crystal masses usually a browny to white color came out of shallow lakes. It forms like a crust in the shallows. messy stuff to dig out and very soft and sometimes only just held together. Its very very soft and the crystals can be ever so delicate.

Many other types of gypsum formations are found on the Australian opal fields like Coober Pedy, Lightning Ridge, Yowah etc. They all used to be sea millions of years ago and the gypsum there can form in like flowers, even opalised sometimes, in white and transparent sheets, and fibrous white seams is the most common sometimes a foot or more thick. And in crystaline shapes in all sorts of patterns. Its also found a lot along some of our coastlines in the shore walls in seams.

There's really no danger in handling any of this material as its just common old gypsum! Some companies crush it up here in Australia and farmers use it as a mineral additive to the soil. No mystery in that.
avatar Re: Australian Selenite question
May 10, 2012 04:14PM
Howdy All,

Most of the green variety are from the settling ponds, and flooded open pit of the West Lagoon mine. However, some pale green specimens have been found in Pernatty Lagoon near the West Lagoon mine site (most likely due to leaching of copper based elements from the mine site into the lagoon area or spillage of copper carbonate specimens from the mine dumps onto the lagoon shore).
The West Lagoon mine is adjacent to the shoreline of Pernatty Lagoon, the Mount Gunson mine (Cattle Grid and etc. names) is located some 3.2km wsw of the West Lagoon mine (and 3.5km w of Pernatty Lagoon).

Cheers Mark.

We will never have all the answers, only more questions!
Re: Australian Selenite question
August 19, 2012 11:21AM
Hi All
This seems to be an old topic
I am the most active legal miner of selenite and have a mining lease on the west lagoon mine that has been isolated from Pernatty lagoon .
I also have mining leases in Bolton Victoria ,and Towan pains (in application ) Victoria
The green colors occurrence is due to the copper is solution changing the ph causing the iron in solution to go from Fe2+ to Fe 3+
Which is actually green . This occurs very rarely , commonly the gypsum is orange ,. If it rains and there is a rapid warming the gypsum goes white
Hence you get orange or green with white caps ,
The gypsum can rapidly dissolve and regrow
There are about 5 lagoons that produce selenite , the last green occurring due to pumping of solution from one point to another trying unsuccessfully to extract the copper
causing green gypsum to occur is a different poundage
Much of the green gypsum sold in Europe is illegally collected from Bolton in Victoria , Theses specimens are white naturally and colored green or pink by a European collector
A lot of Bolton material was collected illegally over the last few years and sold by a very well known Australian dealer.
Police search warrants were served on two properties , with over 12 tonne of Gypsum , lapidary stone and fossil Crinoids were seized .
Charges were laid on one dealer and he plead guilty on a lesser charge arising from this activity .
The other dealer claimed he had no knowledge of these thefts even though he paid for their storage ,and had sold numerous specimens to clients
There are current police ongoing investigations.
I need help in locating the selenite encased shoes that was displayed by Ausrox in Tucson , a few years ago .
The origin of this this specimen is in question .
Having approached a certain dealer at the Tucson show in USA over missing selenite rams skulls , one of which was on display on his stall
I was very rudely told to get F..Ked
David Holderness who is no longer with us , had explained to me and the police how he was employed to raid and steal from my leases in Victoria and
WESTERN AUSTRALIA .
Some of these specimens are still for sale in USA
I have been reluctant to bring these issues forward , but there has been a degree of obstruction accessing records that the police has requested and have not been forthcoming
If any body is in doubt I can forward copies of documents and photos of my claims
Australian Selenite question
September 26, 2012 02:01PM
I have quite a bit to say about this post from Tom Kapitany! I'll keep most of it for later.

Kapitany makes a lot of insinuations without any evidence.

I am the person who was charged with theft of gypsum. There was no conviction.

I can categorically say that I did not remove one piece of gypsum from Kapitany's lease or from the adjacent reserve.

The 12 tonnes of seized stones & gypsum he speaks about were not stolen, nothing was proved and any insinuation of impropriety on the part of a competitor is unfounded.
avatar Re: Australian Selenite question
September 26, 2012 03:17PM
I'd like to ask Tom, under which 'name' is the West Lagoon lease listed? As a search of the records do not show him having any lease in South Australia.

Cheers Mark.

We will never have all the answers, only more questions!
avatar Re: Australian Selenite question
September 26, 2012 06:34PM
I also find it deplorable that Tom is using this forum to make all these false accusations. I work with Ausrox, whom I have worked for many years and know is as honest as they come, when in Tucson and know first hand the trouble that Tom causes. He is constantly sneaking around spying in on dealers and making totally unsubstantiated claims about theft from his "claims" trying to ruin their reputations. To hear him talk you would think he owns all of Australia. His comments have no place in a forum like this and should be deleted. This was a question about how they are formed not a soapbox for Tom to spread his false accusations. His comment should be deleted.



Edited 2 time(s). Last edit at 09/26/2012 07:00PM by Donald Slater.
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