Labradorite, a rock that consists of aluminum, calcium, and sodium silicates. It is a variety of feldspar, found in dark gray crystalline masses that are easily split into slabs. Some varieties of labradorite are beautiful when polished, showing rich shades of blue, green, and bronze. Labradorite is used for table tops and for small ornamental objects. It is found in parts of Europe and the United States, but the finest grade occurs in Labrador.
Sometimes dinosaur fossils are too large and heavy to display without damaging them. How are those enormous models built? And what makes them look so realistic?
La Brea Tar Pits, an area in Hancock Park, Los Angeles, where there is a natural accumulation of sticky asphalt derived from an ancient petroleum seep.