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In the Permian geological age, between 248 and 300 million years ago there was, on the North and Northeast regions of Brazil, a region of lakes and inland seas surrounded by lowlands with primitive vegetation. Giant ferns (Psaronius) predominated, along with proto-conifers (Cordaites), cycads, calamites, etc. This region is now known as the Maranhao Sedimentary Basin, and extends from the Para State, through Tocantins and Ceara. During this period, primitive animals began to evolve. Amphibians similar to mammals (labirintodontus) and reptiles, precursors to the dinosaurs, began to emerge.

Since the region was in constant subsidence (lowering of the Earth's crust), the lakes and seas frequently covered the dry terrain with a very large amount of sediments. The large rivers and torrential rains, together with the sediments, constantly buried trunks and branches from higher land together with the vegetation from the lower areas. The volume and speed of sedimentation formed a thick layer of sediments which reduced the oxygen in the buried vegetation, preventing its decomposition. This gave rise to the process known as mineralization or silicification.

In this process the water retained in the layer of sediments grows rich in silica and, percolating through the vegetable remains, slowly replaces the organic matter with mineral silica, which recrystalizes in silex. As this process is slow and the replacement occurs molecule by molecule, the vegetable matter is completely "copied" by the mineral substance, preserving both its outer appearance and its internal structure, including microscopic aspects such as cells and their nuclei.

Later, over a period of millions of years, this land resurfaces, causing the erosion which today exposes the silicified plants. Because of their resistance, they remain at ground level. These trunks are now found in various regions of the world. The ones shown here come from the Araguaina-Filadelfia mining area in the state of Tocantins. The mine is operated in complete compliance to the country’s environmental and mining laws.

This material has many applications in its rough state, in terrariums, fresh and seawater aquariums, and for decorative purposes, producing effects of singular beauty. Cut and polished, it shows the internal texture and colorations of the various woods, and can be used to make numerous types of jewelry, decorations, and utilities.

Using petrified wood has many advantages. Silica, which petrified wood is made of, is a stable substance. In aquariums, for example, it does not interact with its environment and does not decompose, unlike organic material. For decoration, the fossils are plants which last forever but retain their original internal and external appearance, and each piece is unique.

Another relevant aspect is the variation in size, ranging from a centimeter to meters in diameter. The largest pieces weigh more than a ton.

For industrial uses, its hardness and degree of crystallization are important. Petrified wood can be polished to give an excellent shine. Also, it shows the texture of wood and comes in the most varied colors, as can be seen in the "Sales" section.