The unreal beauty of the agate
There is no other area of Europe which compares to the Idar-Oberstein region
where agates of the most diverse forms and colors can be found. These
treasure-troves of agates were the basis for development of the gem industry
that has kept its prominence until the present, even after the local deposits
were exhausted during commercial mining between 1375 and 1875. Today, raw
stones are imported there from all over the world.
The origin of the agate lies in the
at the end of the earth's Paleozoic era, 285 million years ago, and can be traced
back to the pronounced volcanic activity of the Nahe valley at this time.
Smoky quartz, amethysts, jasper and calcite were also created by this
volcanism. Agate —a special form of the mineral quartz— fills cavities in
volcanic stone. The reason why SiO2 collects in these cavities and is
transformed into agates is still unexplained.
For further information: Landmesser M.,
Zur Geothermometrie und Theorie der Acchate, Mitt. Pollichia 79, 1992: 159-201