Crocoite: Spanning Serbia and Tazmania

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PinkDiamond
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Crocoite: Spanning Serbia and Tazmania

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This is a great article that will tell you everything there is to know about crocoite, and it has pics of some really awesome specimens that are the best I've ever seen. Crocoite is another one on my to-get list that I still don't have a specimen of, and now that I know it's in Oz, I'm thinking that's just another reason to visit the land down under. ...one of these days. ;)

Hope you enjoy this information-packed article from Rock & Gem. :)

Crocoite: Spanning Serbia and Tazmania
By Admin - March 28, 2019

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A superb example of fragile crocoite successfully mined from the Adelaide mine, Tasmania. (John Cornish specimen)

By Bob Jones


"One of the most beautiful minerals we can own is crocoite, a bright red lead chromate. It is also one of the more fragile minerals to mine, handle and own. But its vibrant orange-red color and long slender crystals in elongate, striated, reticulated aggregates rival just about any other mineral for display appeal.

Fragile and Fanciful Mineral

Crocoite was first found in the Ural Mountains of Czarist Russia. Its discovery was made when gold was found in abundance within the middle Urals in about 1745. Crocoite was first found in the Tsvetnoi mine in the Uspenska Mountains, on the east side of the Urals about 1766. The nearest settlement of note to the discovery was Berescov or Beresovsk, Sverdlovsk Oblast not far from Ekaterinberg. Note it is not unusual in Russia for a locality to have more than one name and Beresov is no exception. The place has had its name changed a couple of dozen times.

The vibrant red mineral once found in modest crystals seldom over an inch in length was quickly given the name red lead or Siberian Red Lead. Specimens of the mineral were set to Paris for study, where Louis Nicolas Vauquelin and another scientist worked on the mineral but mistakenly reported that it contained aluminum. Vauquelin was not satisfied with the results, and in 1797 began a long and tedious experiment to isolate the mineral’s contents.

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Only because of a soft limonite matrix can large crocoite specimens like this be successfully collected. (Private collection)

It took more than a year, but in 1798 Vauquelin did prove that Siberian Red Lead contained a new metal element he named chromium. We now know this element as the shiny metal on chrome goods and as one of the most active transition metal elements that causes colors in some gems and minerals.

The Beresovsk deposits are considered the type locality for crocoite and also designated the locality that produced the mineral that was used to prove chromium as a new, discrete metal element. It is unfortunate that these Uralian mines are also where, in 1917, Russia’s ruling Czar and his family met their death.

Crocoite Found In Gold Mines

A large number of the gold mines in this Russian area produced crocoite but never in sufficient quantities to satisfy mineral collectors’ wishes. Fortunately, this deficiency was remedied when it was discovered in Tasmania, in an area that at the time was a prison colony, in the middle 1800s. This resulted in a concerted prospecting effort, and slowly other deposits of tin as well as silver and lead were found. In the area known as Dundas, which was very remote, lead deposits were found, and eventually amounts of red lead were encountered.

By the 1790s, crocoite began showing up in quantity. It was never a significant ore of lead, but specimens were recovered to supplement the Russia crocoite supply. When lead and silver mining in the Dundas area ceased, so did the supply of crocoite, and the area slowly deteriorated and was abandoned. Things remained as such until the 1950s, when specimen collectors began searching the Dundas area.

Largely credited with persistently searching for and finding crocoite was a fellow named Frank Mihelowitts. Frank began collecting and selling crocoite to such a degree that he eventually was given the name “Mr. Crocoite” by major Australian collectors like Albert “Chappie” Chapman. Chappie, a delightful gent and perhaps the most active mineral collector in Australia, was a regular in the early days of the Tucson Show. On a visit to Australia, I was able to see Chappie’s collection on display in a small museum at “The Rocks,” which is a shore-side landing in Sydney harbor where convicts were off-loaded from England in the old days. ... "

https://www.rockngem.com/crocoite-spann ... oite032819
PinkDiamond
ISG Registered Gemologist


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