contaminant
a polluting or poisonous substance that makes something impure
water scarcity
a lack of sufficient water or not having access to safe water supplies
streak
the color of a mineral in its powdered form
water cycle
describes the continuous movement of water on, above and below the surface of the Earth through precipitation, condensation, evaporation, and runoff
hardness
the resistance of a mineral to scratching
luster
the overall sheen of a mineral's surface
mixture
the physical combination of two or more substances in which the identities of those substances are retained
pure substance
a substance composed of one chemical element with both definite and constant composition and distinct properties
rock cycle
describes transitions through geologic time among the three main rock types: sedimentary, metamorphic, and igneous