Mineral Science

Quick answer: Crystal habit is the overall shape a mineral’s crystals take as they grow: prismatic, tabular, acicular (needle-like), bladed,

Quick answer: A phantom quartz crystal contains the outline of an earlier, smaller crystal inside it. The phantom forms when

Quick answer: A geode is a hollow, roughly round rock with a crystal-lined cavity inside; a nodule is a similar

Quick answer: Most crystal colors come from trace elements present at parts-per-million levels. Chromium makes ruby red and emerald green;

Quick answer: A pseudomorph is a mineral that has taken the exact outer shape of a different mineral it replaced,

Quick answer: The Mohs scale ranks minerals from 1 to 10 by scratch resistance: talc 1, gypsum 2, calcite 3,

Quick answer: Fluorescence is when a mineral absorbs invisible ultraviolet light and instantly gives it back as visible color, stopping

Quick answer: Smoky quartz gets its brown-to-black color from natural radiation acting on trace aluminum in the quartz crystal, not

Quick answer: Fire opal is named for its body color, yellow, orange, or red like fire, not for flashes of