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Lesson #1 The Scratch Test Follow these simple steps to get started working on your first million....pieces of gravel? Objective: Gold is a mineral A mineral is a naturally occurring substance which has a unique molecular structure and physical characteristics. Gold miners use a set of simple teststo test these characteristics and to identify the different minerals. Here are some easy ones to try out - get some minerals and see if you can figure out what they are. The Scratch Test: Moh's ScaleMineral hardness is determined by a relative scale called the Moh's Scale. It is relative because ten minerals - chosen from the softest to the hardest - are used to compare or relate each other to. To perform this test, see if one of the the items listed in brackets can scratch the mineral (the item should be able to scratch the mineral it's beside and everything with a lower hardness.)
Gold has a hardness of 2.5 to 3 on the Moh's Scale. The Luster TestThe luster test is used to describe the way the mineral's surface reflects light. There are two general categories: metallic and non-metallic. Luster can vary within a sample of mineral or change depending on your angle of view. Here are the categories for non-metallic lusters (metallic lusters are just classified as "metallic"):
Gold has metallic luster.
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