Raw Emerald first appeared in the Second Edition of the Mini Museum. We are happy to offer it once more as a stand-alone specimen as part of our Gem and Minerals Collection.
Above: Front of specimen card featuring a miner from Muzo, Colombia, his hands vividly demonstrating the intensity of Carboniferous rock in which these treasures are found.
"A casual glance at crystals may lead to the idea that they were pure sports of nature, but this is simply an elegant way of declaring one's ignorance." ~ René-Just Haüy, father of modern crystallography who first classified the emerald as a beryl in 1797
We often hold up purity as the chief virtue of the rare and beautiful, but in the world of crystals, it is the impurity that often sets the gemstone apart and makes it desirable. On its own, beryl is a colorless crystal, but with the addition of a chromium impurity, the mineral becomes a brilliant green emerald - one of the rarest of all gemstones.
Above: Macro image of raw emerald specimens.
This specimen is a raw emerald from the Muzo region of Colombia. The specimen is housed in an acrylic jar that is encased within a glass-topped riker display box. The box measures 4 1/2" x 3 1/2". A small information card is also included, which serves as the certificate of authenticity.
More about Emeralds
Heat, pressure, time, and the influence of water are the primary components in gemstone formation, but there are many possible combinations. In the case of quartz and beryls, the process involves rapid cooling and crystallization of mineral-infused hot water vapor, pushed up through layers of rock by the presence of magma below.
Many gem-producing hydrothermal regions exist around the world, but the emerald producing areas of Muzo and Chivor in the mountains of Colombia are different.
Above: The rugged and mountainous areas of Muzo and Chivor are comprised of black, carboniferous shale dating to the Lower Cretaceous. This rock was invaded by hydrothermal mixtures which cooled to form white calcite veins. It is here in the calcite veins that Colombian emeralds are most commonly found.
Documented evidence of mining in this region dates back to the Spanish conquest, but archeologists have also discovered evidence that humans have been digging emeralds of unsurpassed quality out of these rugged hills for much longer. The most abundant areas for emerald mining are in the mountainous regions of Muzo and Chivor. In indigenous myth, the Funa and Tena peaks near the Muzo mines are said to be the source of emeralds when the tears of the Fura were turned to gems.
While in most parts of the world emeralds are often found in igneous deposits, this is not the case for Colombia. Here, emeralds appear in black, carbon-rich shales. Hydrothermal brines permeate these areas, causing the release of chromium, vanadium, and beryllium, which together form the green gem. This process washes away iron from the formation, causing the emeralds here to be the greenest in the world.
Above: Back of specimen card.