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invention category A group or set of inventions that are classified together because of common characteristics. Invention groups that include Agricultural, Communications, Computing, Energy, Transportation and more.
Scientific Classifications of Mineral Groups. Scientific Classification. **Minerals and gemstones are classified according to their chemical compositions. There are eight classes, along with a ninth class for non-minerals, which may be non-crystalline organic combinations and/or rocks.The nine classes are listed below with examples of a few of the individual species within these groups. group of minerals that are compounds of one or more metallic elements associated with the Phosphate radical. They are classified together with the Arsenates and Vanadates. They are usually brittle and occur in small crystals or compact aggregates.