Igneous Rocks

Notes in this section

• Basalt

  Wikimedia Commons Basalt Igneous Hardness: ≈6 Approximate BasaltGraniteObsidianRhyolite

• Granite

  Wikimedia Commons Granite Igneous Hardness: ≈6–7 Approximate BasaltGraniteObsidianRhyolite

• Obsidian

  Wikimedia Commons Obsidian Igneous Hardness: 5–6 BasaltGraniteObsidianRhyolite

• Rhyolite

  Wikimedia Commons Rhyolite Igneous Hardness: ≈6–7 Approximate BasaltGraniteObsidianRhyolite