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/
8
CH1012
SILICATES
Silicate minerals are based on the
repeating unit
[SiO
4
4-
]
.
•
Silicates other than quartz
are
anionic
, with counterions
incorporated in the structure
to balance the charge.
eg Al
3+
beryl
Be
3
Al
2
Si
6
O
18
kaolinite
[
Al
2
Si
2
O
5
(OH)
4
]
2
Si
2
O
5
2-
sheet silicate
- clay