Skip to content
New issue

Identify All Glassy Rocks and Display Identified Rock List

Past due by almost 6 years 50% complete
  • Glassy (no visible grains)
    • Is it light or dark?
      • Light is Igneous - Quartz.
      • Dark is Igneous - Obsidian.
  • Fine Grained (not easy to see grains)
    • Can the rock be stratched by a knife?
      • Yes, and it is dense and brittle - Sedimentary - Chert.
      • No
  • Glassy (no visible grains)
    • Is it light or dark?
      • Light is Igneous - Quartz.
      • Dark is Igneous - Obsidian.
  • Fine Grained (not easy to see grains)
    • Can the rock be stratched by a knife?
      • Yes, and it is dense and brittle - Sedimentary - Chert.
      • No
Loading