Araucaria Fossil Wood Pietrified Trunk Branch Tree Plant Conifer Mesozoic Triassic Collection (4)

Silicified Fossil Trunk Conifer Wood mm 73 x 48 x 30 gr 137 Fossilized Branch Araucaria sp. Plants Logs Trees Petrified Plants Extinct Gymnosperms Mesozoic Triassic Collecting Paleontology Botany Museum.

Pleasant fossil find of a petrified portion branch of Araucaria Conifer from the Upper Triassic of Madagascar, a representative collectible sample of best quality, with clear details of the structure of silicified external bark and of the growth rings, highlighted on the upper side which has been specially polished, thus accentuating the original color, remained perfectly preserved.
Only a piece, as in photo.

Petrified Wood is the name given to Wood that has been transformed into stone (fossilized) through the process of Permineralization. In this process, all organic matter is replaced by minerals, while much of the original structure is retained.
For this to happen, the wood must be buried in an anoxic (oxygen-poor) environment to prevent decay, and with running water rich in minerals, so that these can replace the organic matrix. The coloration is caused by various minerals present in that water during fossilization. For example, red colors are due to iron compounds, greens are due to copper, and so on.

Araucaria (Juss 1789) is a genus of evergreen Conifers in the family Araucariaceae which includes about a dozen still existing original tree species in the southern hemisphere, and more than a dozen recognized extinct, once widespread throughout Gondwana.
The genus name is derived from Araucanos, indigenous tribes of Chile.
Araucaria are mainly large trees with a massive erect stem, reaching a height of 30-80 meters. The branches, horizontal diffusion grow in vortexes and are covered with leathery or needle-like leaves.
There is no distinct common name for the genus, but most often is called "pine", although they are only distant relatives of the true pines (Pinus).
Members of existing Araucaria are found in South America and Oceania. Many if not all current populations are relicts, and of restricted distribution. These columnar trees are living fossils, dating back to the Mesozoic Era. Fossil finds show that the genre in the past was also widespread in the Northern Hemisphere to the end of the Cretaceous period.
There is evidence to suggest that the long necks of Sauropods dinosaurs may have evolved specifically to prune the tree tops, typically very high, of Araucaria. The global distribution of the vast forests of Araucaria during the Jurassic makes it likely that they were the main energy source of food for the giant sauropods adults.
Her are some recognized extinct genera:
† Araucaria nipponensis - Japan
† Araucaria brownii - England
† Araucaria mirabilis - Patagonia
† Araucaria sphaerocarpa - England
† Araucaria haastii - New Zealand
† Araucaria lignitici - (Paleogene) Yallourn, Victoria
† Araucaria vulgaris - Japan
† Araucaria desmondii
† Araucaria fibrous
† Araucaria beipiaoensis
† Araucaria nihongii - Japan
† Araucaria taieriensis - New Zealand
† Section Perpendicula. Contains only one specie
† Section Yezonia. Contains only one specie