MOLDAVITES
What is Moldavite?
Moldavite is a mysterious green glassy stone of cosmic origin which can only be found in the Czech Republic. It was virtually unknown in the gem world a few decades ago. Now, as it becomes increasingly more rare, it is sought after around the world.
Formed millions of years ago through a devastating astroid impact, they are far more rare than diamonds. These cosmic stones come in a huge variety of shapes, sizes and textures. The colors vary from forest and golden greens, to brown and the rare emerald "poison" green.
Since their rise in popularity in the late 90’s, most of the commercial deposits of Moldavite have been mined out. As the demand grows and supply dwindles, the usual fake synthetic moldavite from China have inundated the market. This is a travesty for those looking for the real deal.
The Origin of Moldavite
Origin
Moldavite was formed during a celestial event some 15 million years ago. A huge astroid estimated to be around 1 km in diameter struck southern Germany and formed what is today known as Ries Crater. This event would have caused an explosion hundreds of times that of Hiroshima, flattening the area for miles around.
This molten material was ejected into the upper atmosphere. On its way up, the future moldavite stones under went intense heat, tension and centrifugal forces, creating the initial shapes of discs, spheres and other splash forms. In the final phase, the stones cooled rapidly as they fell to earth, in what is today the Czech Republic.
It is estimated only 1% of the initial Moldavites born from this event, survive today. Millions of years of shifting sediments, and natural erosion of the stones have claimed the rest.
The largest deposits of Moldavite have been found in the upper Vltava River basin between Prachatice and Trhovým Sviny, especially to the south and west of České Budějovice (Budweis), Czech Republic. Moldavites have also been found in Moravia, mainly in the central area of the river Jihlava. Stones from this region are sometimes referred to as Moravita, and have a brownish color and are, on the whole, not as desirable as their green Bohemian siblings. Other less significant Moldavite sites have been discovered in neighboring Austria.
The Science of Moldavite
ording to modern scientific concensus on the origin of Moldavite, ~ 15 million years ago a huge astroid at least one kilometer in diameter, struck what is now southern Germany from a westerly 56 degree angle at a hypervelocity, creating the Ries crater, 15 miles in diameter. The impact melted the stratus of sediments and rock at a depth of 2,000 feet and ejected the material into the upper atmosphere.
The crater ejection material had a high content of silicon dioxide and underwent intense heat of approximately 30,000 C before it was ejected in its molten state into the upper atmosphere. At this point, the Moldavites underwent plastic deformation as they interacted with the aerodynamic forces under intense surface tension. They underwent ablation and more shape deformation on their return to earth. Many Moldavites were shattered do to their internal pressure or fractured upon impact.
Most bubbles in Moldavite are thought to have formed from gases released from the host rock during impact. Elongated bubbles are said to have formed during the cooling down stage as the stones returned to earth. Lechatelierite, a pure form of SiO2, is formed when quartz undergoes an intense transformative heating process. The beautiful flow forms and fluvial structure of Lechatelierite is found in virtually all Moldavites. It gives Moldavite its unique internal structure and is one of the main ways we can identify genuine Moldavite from fakes.
The texture of Moldavite varies drastically, but it is caused from a combination of the ablation phase during the stones descent and natural corrosion process over millions of years in various conditions. Stones from more sandy acidic soils often have a more lacquered appearance with a bright, glassy appearance. Stones found in more clay alkaline soils have a detailed pyramidal micro-sculptation which creates a velvety luster. Other field stones that are collected which have been found close to the surface, sometimes have their texture worn away completely like a river rock.
