A really well preserved fossil wood slice from Madagascar. Period Lower Jurassic. Beautiful colors, evident and beautifully preserved wood texture, truly excellent quality. Note the beautiful mineral crystallization created over millions of years inside the cracks of the wood This is a wide round of petrified wood (Araucaria) from Ambilobe, Madagascar. Araucaria is a coniferous tree in the family that includes the modern Monkey Puzzle tree. This 220 million year old petrified wood has been sliced and polished on both sides, allowing the stunning inner wood detail and beautiful coloration to easily be seen. Petrified wood is the name given to wood that has been turned into stone (fossilized) through the process of permineralization. In this process, all of the organic matter becomes replaced by minerals, while much of the original structure, such as tree rings, is retained. For this to happen, the wood needs to be buried in an environment low in oxygen to prevent decomposition and with flowing, mineral-laden water, so minerals may replace structures. The coloration is caused by various minerals/impurities present in the water during fossilization. For example, red colors in many cases can be attributed to iron compounds, greens due to copper, and so on