Geology Reference
In-Depth Information
5. Volcanics 2-Pyroclastic Rocks
4. Volcanics 1-Lava Flows
3. Igneous Textures & Classification
2. Field Skills & Outcrop Structures
1. Introduction and Occurrence
Table 3.4
(continued)
Mineral
Typical chemical
formula
Colour
Cleavage
Lustre
Habit
Hardness
Zeolite group
For example,
(Na
2
Ca)
(Al
2
Si
3
O
10
).
n
H
2
O
White, pale yellow or
pale green, rarely
pink, red or blue
Va r i a b l e
according to
mineral type
Usually
vitreous or
silky
Massive or granular crystals
lining cavities, particularly,
amygdales; radiating fibrous
5-6
