Determining the Difference Between Fluorite and Quartz

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  Use a knife to scratch the minerals.a sharp utility knife image by timur1970 from Fotolia.com
  
  Scratch the rock with a utility knife to determine its hardness. Hardness is determined using Moh's Scale. Fluorite is a four on the hardness scale, whereas quartz is a seven, which is much harder. Fluorite will scratch if you scratch it with a normal knife blade because a blade has a hardness of 5.5. Quartz will not scratch if you try to score it with a knife blade.
  
  
• 2
  Use the rocks to score glass.red glass green glass image by Roman Kyrychenko from Fotolia.com
  
  Scratch a piece of glass with the rock. Fluorite will not scratch glass because it is not hard enough. Quartz is harder than glass and will scratch the glass.
  
  
• 3
  Use safety precautions when working with a hammer.the hammer image by Jim Mills from Fotolia.com
  
  Use a hand lens to examine the crystal structure of the rock. If possible, use a hammer and a piece of fabric to break a small piece of the mineral. Put on your safety goggles and place the fabric over the rock. Hit it with the hammer. Quartz will break into shards that are curved, while fluorite crystals have a clean, eight-sided break. If the rock is unbroken, the fluorite crystals will often form cubes.