Most common minerals in igneous rocks

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Observe & Discuss:

Station - Identify the following igneous minerals

  • Quartz - Assortment of colors, scratches glass and feldspar

  • K feldspar - Pink, white and blue with perthite

  • Plagioclase - Multiple shades of white to gray, striations

  • Mica - Biotite and muscovite, flaky

  • Amphibole and pyroxene - Dark with distinct cleavage

  • Olivine - Green and granular

Are these minerals commonly found in sedimentary rocks?

What is a crystal?

How many crystals are in each sample?

  • Single crystal - One

  • Diorite - Many

  • Obsidian - None

  • Basalt - Many more than in the diorite

Moon rock