Wonderstone; From Tooele County, Utah is a welded-vitric tuff (vitric means glassy) of rhyolitic composition. It is a volcanic rock composed predominantly of volcanic glass particles which have been welded or stuck together by heat and compacted by the weight of overlying material. Alteration of the rock by circulating ground water produced the colorful banding. The maroon and yellow-brown colors are due to the presence of iron oxides. This stone has shades of red, yellow, and cream. A prefect example of Wonderstone, its polished front and back.
Size: 44.5mm X 25.2mm, Dome: 4.4mm
Weight: 6 grams