Plate Tectonic Cycle - Volcanoes (K) Quantity in Basket: none Code: PT-VK Price: $5.25 Shipping Weight: 2.00 pounds Quantity: Learn that volcanoes produce rocks and that volcanic rocks produce different types of rocks. Module contains basalt, sea urchin spine, pumice, diatomite, obsidian, styrofoam, and sea cookie. (code PT-VK)