Rutile ↗
Mineral species
Rutile may be red-brown, dark or needle-like, with strongly reflective surfaces. Looking at rutile itself is a useful companion to studying needles enclosed in quartz.
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Crystal Guide / All families
Same formula, different crystal structures
Titanium dioxide polymorphs.
Rutile, brookite and anatase all have TiO₂ chemistry but distinct structures and species identities.
Keep each chapter’s scientific identity: a family, species, variety, trade label, rock and fossil are different kinds of names.
Brookite ↗
Mineral species
Brookite is a titanium dioxide mineral, often brown to dark in collector crystals. Thin areas can show a lighter reddish-brown tone.
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Mineral species
Anatase is another titanium dioxide species, often found as small, sharply shaped crystals. Blue, brown and nearly black appearances occur.
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