Showing posts with label crystals. Show all posts
Showing posts with label crystals. Show all posts

Friday, May 28, 2010

The Tsumeb Mine - A Crystal Paradise


Cerussite 'Honeycomb'



Cerussite (red) with Bayldonite and Calcite



Smithsonite with Hydrocerussite



Calcite with Cuprite inclusions



Malachite on Dolomite



Azurite on Cerussite



Cuprite on Copper

The Tsumeb Mine is arguably the finest mineral locality ever discovered. The ore-body produced a diverse range of specimens and spectacular crystals which were, and still are, sought after world-wide.

This website says of the Tsumeb orebody:


"Tsumeb offers one of the greatest varieties of mineral assemblages known. It produced 247 known species, plus 24 species still under investigation.

Of the minerals discovered in Tsumeb, 45 are known to occur solely there. But not only the rare finds boast of superlatives. The crystallization of most minerals is so perfect and aesthetic that 68 species from Tsumeb display the finest crystals known from any deposit.

Many localities have produced specimens generally considered to be the finest of the species ever found. However, most of the localities are known only for one or two species of this quality.

In comparison, Tsumeb exhibits more outstanding mineral specimens than most localities even contain minerals. These minerals provide the quality benchmark for every collector."

As I explained in an earlier post, I worked as a miner for 12 years at the Tsumeb Mine and during that time I was privileged to see many examples of these spectacular crystals.

I've stood in vugs surrounded by crystals, jewels glittering in my headlamp. I've seen men shiver with greed, fight over and risk their lives to get them - 'crystal fever' - and in truth, I was also overwhelmed on occasion, though not to the extreme I've just described.

The removal of mineral specimens was always a murky and controversial issue. Although it was considered theft and people could be fired if caught, everyone from laborers to managers carried them out.

There was a constant stream of European and American buyers in town, offering big bucks for top pieces.

The official policy was that the purpose of the mine was to mine ore, not preserve mineral specimens but, if found, miners were 'expected' to save and hand them over to the 'Company', so that they could be sold on auction - with no reward to the finder.

This presented a problem to those who also appreciated the specimens for their aesthetic value - it was unthinkable to just leave these unique crystals to be dumped into an ore-pass, to be destroyed in the crushers.

On the other hand, if they were handed over to the company, the best pieces would be skimmed off by greedy hands long before they reached any auction.

Today, twelve years years after the closure of the Tsumeb mine, the saddest aspect is that there are very few spectacular specimens in Namibia itself - most are to be found in private collections and museums overseas.

The first image is from the Sussman Collection and the rest from the John Schneider Collection - more specimens via Arkenstone Fine Minerals

All photos in this post by John Schneider.


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Saturday, February 20, 2010

Spectacular Crystal Cave

Image Credit: Unknown
Cueva de los Cristales

Wiki says that the Cueva de los Cristales is a cave connected to the Naica Mine 300 metres (980 ft) deep in Chihuahua, Mexico.

The main chamber contains giant selenite crystals, some of the largest natural crystals ever found.

Image Credit: Unknown
The cave's largest crystal found to date is 11 m (36 ft) in length, 4 m (13 ft) in diameter and 55 tons in weight.

The cave is relatively unexplored due to the extreme temperatures and high humidity. Without proper protection people can only endure approximately ten minutes of exposure at a time.



Image Credit: National Geographic
Having worked for twelve years as a miner in one of the world's most famous mineral localities, I find this truly spectacular ...

... I've seen vugs of bright, shiny jewels and stood in caves completely surrounded by crystals but, I've never seen anything like this.

And those extreme temperatures, I know exactly what they mean.

Here's a link to an excellent photo set which will give you a better idea of the scale.


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