Jump to content

File:Digenite-pyrite, Butte Mining District, Montana.jpg

Page contents not supported in other languages.
This is a file from the Wikimedia Commons
From Wikipedia, the free encyclopedia

Original file (2,192 × 1,578 pixels, file size: 2.64 MB, MIME type: image/jpeg)

Summary

Description

Digenite-pyrite hydrothermal vein sample from Montana, USA. (SDSMT 2125, South Dakota School of Mines and Technology Museum of Geology, Rapid City, South Dakota, USA)

Very dark blue = digenite Brassy gold = pyrite

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 4900 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The sulfide minerals contain one or more sulfide anions (S-2). The sulfides are usually considered together with the arsenide minerals, the sulfarsenide minerals, and the telluride minerals. Many sulfides are economically significant, as they occur commonly in ores. The metals that combine with S-2 are mainly Fe, Cu, Ni, Ag, etc. Most sulfides have a metallic luster, are moderately soft, and are noticeably heavy for their size. These minerals will not form in the presence of free oxygen. Under an oxygen-rich atmosphere, sulfide minerals tend to chemically weather to various oxide and hydroxide minerals.

Digenite is a scarce copper sulfide mineral, Cu9S5. It has a metallic luster, dark bluish-gray to blackish color, dark gray streak, and a Mohs hardness of 2.5 to 3. It’s usually massive, but can form pseudocubic crystals. Broken surfaces show conchoidal fracture. Primary digenite occurs in some copper-bearing hydrothermal veins, some intrusive igneous rocks, and in some sulfide exhalative deposits.

The digenite sample shown above is from Montana's Butte Mining District. In this area, digenite occurs in 62 to 66 million year old copper sulfide-rich hydrothermal veins that intrude the Butte Quartz Monzonite, a pluton of the Boulder Batholith (mid-Campanian Stage, late Late Cretaceous, 76 million years).

Locality: Butte Mining District, Silver Bow County, southwestern Montana, USA


Photo gallery of digenite:

www.mindat.org/gallery.php?min=1291
Date
Source Digenite-pyrite (latest Cretaceous to earliest Tertiary, 62-66 Ma; Butte Mining District, Montana, USA)
Author James St. John

Licensing

w:en:Creative Commons
attribution
This file is licensed under the Creative Commons Attribution 2.0 Generic license.
You are free:
  • to share – to copy, distribute and transmit the work
  • to remix – to adapt the work
Under the following conditions:
  • attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
This image was originally posted to Flickr by jsj1771 at https://www.flickr.com/photos/47445767@N05/17586843154. It was reviewed on 12 June 2015 by FlickreviewR and was confirmed to be licensed under the terms of the cc-by-2.0.

12 June 2015

Captions

Add a one-line explanation of what this file represents

Items portrayed in this file

depicts

19 August 2010

2,771,049 byte

1,578 pixel

2,192 pixel

image/jpeg

fce311a3ab83e2716bc16c52a56211ae501f554b

0.025 second

35.7 millimetre

File history

Click on a date/time to view the file as it appeared at that time.

Date/TimeThumbnailDimensionsUserComment
current04:32, 12 June 2015Thumbnail for version as of 04:32, 12 June 20152,192 × 1,578 (2.64 MB)TillmanTransferred from Flickr via Flickr2Commons

The following page uses this file:

Metadata