Is this really wood? Well, it certainly used to be! Petrified wood is a fossil formed when minerals impose themselves upon cavities between and within the cells of natural wood. This process is usually undertaken by silica or calcite, and the replacement of the organic tissue with the minerals can be so precise that the internal structure, as well as the external shape, can still be very well-represented. The result is that the wood takes on a calcified appearance, while still retaining the basic characteristics of the wood, and different minerals can give petrified wood a range of diverse colorations, making each specimen totally and markedly unique. A beautiful example of incredible geological forces, this will be an excellent addition to a comprehensive rock collection in the science classroom, or for the rock collector in your family.
Use this awesome prism to teach about optics and light in the classroom setting!
Discover how solar cells make electricity with this awesome kit!
The Star-Ball Magnetic Puzzle is the perfect creativity tool for innovators, artists, writers, students, and you!
NEW 2016 DESIGN! This hip red tee features Pi to 1000 decimal places on an ultra soft 100% cotton shirt.
A combination of three of our great discovery toys, all in one package!
This is a classic demonstration toy of the powers of magnetic fields!