This is an gorgeous pair of bookends made from kambaba jasper, collected from Madagascar. One side has been cut flat and polished to a glossy finish, while the opposite side has been left rough. The middle of the bookends have been lined with felt and the bottoms have round rubber "feet" to prevent scratching of the display surface.
Each bookend varies slightly in size, with one measuring 6.2" tall, 4.2" wide and 2.5" thick while the other is 6.2" tall, 4.1" wide and 2.7" thick. Together these bookends weigh just over 8 lbs.
Kambaba jasper and crocodile jasper are trade names for a greenish rhyolitic (volcanic) rock found in the west-central Bongolava region of Madagascar. It is full of blackish orbs consisting of small Amphibole needles that some people say resemble amphibian eyes, hence the name "crocodile jasper". There is a common misconception that Kambaba Jasper is a stromatolite
, however this is incorrect as it is volcanic in origin. Despite the misconceptions it is a beautiful decorative stone when polished.
Jasper is a term that can be applied to an opaque variety of chalcedony (light does not pass through it) The opaqueness is due to a much larger amount of impurities mixed with silica/quartz. Like agate it may form in a huge variety of colors, and is often multi-colored. In most cases, jasper will occur when silica-rich fluids permeate throughout a soft sediment or volcanic debris deposit. The fluids then crystallize around the particles/impurities, resulting in a cementation process. Most often, the impurities present determine the coloration of the deposit following solidification, however other factors can play a role in the color of what is now considered a jasper.