| A | B |
|---|
| hydrogen | the element that combines with oxygen to make water |
| oxygen | the element that combines with hydrogen to make water |
| element | a substance of the simplest type |
| chemical symbol | a kind of shorthand used to write the names of chemical elements |
| universal | worldwide, throughout the world |
| compound | a substance made up of two or more elements |
| properties | facts about a substance that help to describe it |
| chemical formula | a kind of shorthand scientists use to give information about chemicals |
| subscripts | numbers appearing slightly below the line in chemical formulas |
| mineral | a material found in the crust of the earth |
| quartz | a mineral made of silicon dioxide |
| physical properties | facts about an object that help identify it |
| identify | tell what something is |
| luster | the amount of shininess of a mineral or object |
| streak | the powder a mineral leaves when it is rubbed |
| mass | a measure of how much matter there is in an object |
| density | the mass of an object divided by its volume |
| cleavage | the splitting of a mineral along a flat surface |
| fracture | the way a mineral breaks along uneven surfaces |
| crystal | a piece of a mineral with a definite shape |
| magnetite | a mineral that is attracted to a magnet |
| ore | a mineral that has a large amount of metal in it |
| gemstones | minerals that show some form of beauty |
| gem | a cut or shaped gem stone |
| corundum | a mineral composed of aluminum oxide |
| ruby | a deep red corundum gemstone |
| sapphire | a blue corundum gemstone |
| carat | a unit of mass for gems, equal to 0.2 grams |
