Color of Sulvanite

Mindat says Sulvanite is "Cream-gold, bronze gold-yellow". None of the photos show sulvanite that color? Why?

Tarnish ? Impurities ?

I have a box full of sulvanite from what I believe to be the World's best sulvanite locality.

An un-named prospect in the Thorpe Hills of North Central Utah.

I can assure everyone that the color in hand specimen is silvery gray exactly like tetrahedrite.

The discrepancy in color description results from old dead men who are describing the color as viewed through an ore microscope with various color filters and polarizers. To them, the color of sulvanite may look creamy yellow compared to tetrahedrite.

Do NOT visit the locality. I want to go back and get some more sulvanite before you do !

Bart



Edited 1 time(s). Last edit at 06/09/2012 09:19PM by Bart Cannon.

Hello Bart,

Have you had it tested?

I have analyzed the sulvanite from Utah many times.

I offer it as a good reference matetial though there are some small spiderwebs of secondary alteration minerals present.

The good stuff is fresh and shows brilliant crystals.up to 4 millimeters when the calcite is etched away..

But don't go there before I go back.. .

Bart

Hi all,

I collect minerals on Carrara Marble and local sulvanite color is exactly like tetraedrite but sometimes covered,
all or partially, by volborthite or malachite or others

Hi Mindat management,

more generally about colour on Mindat, i don't know whether it's my computer/monitor (both pretty standard) but the full information on colour included with a mineral description is often truncated, eg sulvanite "Colour: Cream-gold, bronze ..."

Is there something wrong with my computer/monitor?

thanks

tom

"Is there something wrong with my computer/monitor? "

No.

The mineral page header is conceived to provide quick info on a few properties. Colour will be truncated if the entry in that field is too long, i.e. when there are multiple colours for a mineral. In that case, it is better anyway to refer to the full entry (just scroll down).

Hi Peter,

thanks for that.

By the way, and straying completely off the topic of colour, i wonder if it would be possible to have a field giving guidance on how the names of less familiar minerals should be pronounced. Rarer minerals aren't mentioned in my large standard dictionary. For example is prehnite pronounced praynite or prenite? I know that there is the International Phonetic Alphabet but that's rather difficult for the layperson to understand, and that there might be no easy way to convey the pronunciation of an unfamiliar word. Not too mention all the complexities of American etc vs British English pronunciation.

cheers

tom.

So if sulvanite is the color of tetrahedrite then shouldn't that fact be noted in the description for the mineral. Me thinks that maybe the current description for the color is that which is observed in polished section through a microscope.

From the Handbook:

"Color: Bronze-gold; pale yellow in polished section."

I assume therefore, that the bronze-gold colour was NOT observed in polished section, but on the actual specimen.

[rruff.geo.arizona.edu]

Quote
Type description
Physical properties of the mineral :-Massive, lustre metallic to
sub-metallic, colour bronze-yellow, streak nearly black, hardness 3.5,
sp. gr. 4.0.

[rruff.info]

I am sorry to be a repeat poster on this, but you must believe me. I know of what I speak.

Sulvanite is silvery gray in hand specimen. No ifs, ands, or buts.

I have also observed it many times in polished section. I do not consider it creamy yellow.

Back to the color chart issue.

Bart

From the link to Ruff given by David: "No crystalline form could be detected in the specimens
examined, and this, with the presence of oxidised minerals, renders
the physical properties rather vague."

Sounds like the color was based on impure material. The crystals pictured in the Mindat data base look rather pure and probably represent the true color don't you think?

Hello Bart,

I don't know about that. I think maybe we are both color blind and tetrahedrite is really bronze-yellow.

Riener,

My color perception is considered perfect according to the fabulous publication: "Pseudo-Isochromatic Plates for Testing Color Perception"

From the American Optical Company. I often embarass my artist friends by giving them the tests.

Describing colors is another matter. One that I still wish we could come to a solution about.

Bart



Edited 2 time(s). Last edit at 06/11/2012 01:00AM by Bart Cannon.

The material from the Edelweiss mine in South Australia (type locality) is silver-grey as well. Haven't checked lately what colour a freshly-broken surface of the sulphide is, however.

I have specimens both from Thorpe Hills, UT (xls), and the Edelweiss Mine in Australia (massive), and they're both a steel-grey color.

Lefteris.

Looks like it might be time to change the color on the Sulavanite page. The "old" color could be referenced.

Rock Currier
Crystals not pistols.

Great idea Rock too bad I didn't think of that!