Habit: Terms

1
Habit Terms

• Acicular, Capillary, Filiform, Bladed, Dendritic,
  Radiating, Drusy, Fibrous
• Globular, Colloform, Foliated, Micaceous,
  Tabular, Lamellar, Plumose
• Granular, Columnar, Prismatic

2
Acicular

• slender, needle-like crystals tourmaline,
  hornblende, arsenopyrite, rutile, apatite,
  sillimanite

3
Capillary and filiform

• hair-like or thread-like native Au, Ag, Cu

4
Bladed

• elongated crystals flattened like a knife blade
  kyanite, tremolite

5
Dendritic

• arborescent, in slender divergent branches,
  somewhat plantlike--native metals, pyrolusite

6
Radiating

• divergent zeolite tremolite talc
• pyrolusite, tourmaline

7
Drusy

• surface covered with a layer of small
  crystals--sugar like calcite, quartz,
  sphalerite, pyrite

8
Fibrous

• aspect ratio 101
• chrysotile asbestos

9
Globular and colloform

• radiating individuals forming small spherical
  groups
• examples include zeolites, quartz, malachite,
  goethite, pyrolusite, hematite

10
Botryoidal

• bunch of grapes, example pyrolusite

11
Reniform

• kidney like, examples hematite, malachite

12
Mammillary

• -very large, example is malachite

13
Foliated

• easily separable into plates or leaves
  tremolite hematite

14
Micaceous

• similar to foliated but splits into very thin
  sheets muscovite, biotite, chlorite

15
Tabular or lamellar

• flat and platelike barite, dolomite

16
Granular

• composed of many individual grains of similar
  size olivine, garnet

17
Prismatic or columnar

• elongated crystals with identical faces parallel
  to a common direction tourmaline, hornblende,
  apatite