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Improving Mindat.orgChalcodite

15th Sep 2016 18:47 UTCJohn Betts

The Mindat page for Chalcodite (http://www.mindat.org/min-39169.html) does not state that it is a varietal name for Stilpnomelane. See Dana's 6th, 1892.

15th Sep 2016 19:07 UTCRichard Gunter Expert

Hi John:

Chalcodite is not a variety of Stilpnomelane but is a separate member of the Stilpnomelane Group. There is an ongoing re-organization of that group but I do not believe anything has been published yet.

18th Sep 2016 00:02 UTCRalph S Bottrill 🌟 Manager

We need to describe these minerals better here. Chalcodite says it is ferric-only, while the formula and analysis clearly indicate a significant ferrous iron component. Stilpnomelane says nothing out its oxidation state.

26th Sep 2016 19:49 UTCJohn Betts

What is your reference?

Dana's 6th (1892) says otherwise.

Fleischer's Glossary of Mineral Species does not list Chalcodite as a valid species.

26th Sep 2016 22:41 UTCRichard Gunter Expert

Hi John:

There are several references on the Chalcodite page, unfortunately none later than 1971. The Stilpnomelane references refer to Chalcodite as the ferric analogue of Stilpnomelane. I have seen nothing else.

26th Sep 2016 23:07 UTCMark Heintzelman 🌟 Expert

Must assume this is preliminary inclusion of a "work in progress". Nickel Nichols Mineral reference guide also does not include chalcodite as a valid species, nor as a synonym nor in reference to stilpnomelane (only lennilenapeite is noted). (?) Curious myself.

MRH

26th Sep 2016 23:54 UTCRichard Gunter Expert

Hi Mark:

That is what I have read. I do not know who is doing the investigation but the Stilpnomelane Group is complex enough it may take a bit of time.

27th Sep 2016 00:04 UTCJohn Betts

Since it has not been published, should Mindat list Chalcodite as an IMA-accepted species?

27th Sep 2016 00:40 UTCReiner Mielke Expert

Mindat doesn't it says " Currently not approved by the IMA."

27th Sep 2016 08:31 UTCUwe Kolitsch Manager

It's not contained in the current IMA list.