File:Orpiment (Getchell Mine, Humboldt County, Nevada, USA) 1 (18286769633).jpg

Original file(933 × 766 pixels, file size: 627 KB, MIME type: image/jpeg)

Captions

Captions

Add a one-line explanation of what this file represents

Summary edit

Description

Orpiment from Nevada, USA. (CMNH 19988, Cleveland Museum of Natural History, Cleveland, Ohio, USA)

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.

Realgar and orpiment are both arsenic sulfides. Realgar is an intensely reddish-orangish arsenic sulfide (AsS), while orpiment is a bright yellow-colored arsenic sulfide (As2S3). They are always associated with each other. Arsenic is a rare element in Earth’s crust, but because As has very few uses in modern society, it has practically no value. Orpiment & realgar have a nonmetallic luster and are fairly soft (H=1 for yellow orpiment & H=2 for reddish-orange realgar). The two minerals are fairly insoluble, but they do volatilize readily. When heated, they release a garlic smell (arsenic). Realgar tends to alter to orpiment when exposed at Earth's surface.

Locality: Getchell Mine, northern end of the Osgood Mountains, eastern Humboldt County, northern Nevada, USA


Photo gallery of realgar: www.mindat.org/gallery.php?min=3375


Photo gallery of orpiment:

www.mindat.org/gallery.php?min=3021
Date
Source Orpiment (Getchell Mine, Humboldt County, Nevada, USA) 1
Author James St. John

Licensing edit

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://flickr.com/photos/47445767@N05/18286769633. It was reviewed on 27 July 2015 by FlickreviewR and was confirmed to be licensed under the terms of the cc-by-2.0.

27 July 2015

File history

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

Date/TimeThumbnailDimensionsUserComment
current18:48, 27 July 2015Thumbnail for version as of 18:48, 27 July 2015933 × 766 (627 KB)Natuur12 (talk | contribs)Transferred from Flickr via Flickr2Commons

There are no pages that use this file.

File usage on other wikis

The following other wikis use this file:

Metadata