Chemistry Reference
In-Depth Information
Examples of K-bearing silicate minerals and their dissolution rates (acidic mechanism).
20
(Note that the K
2
O content of
nepheline varies from 3.6-12.2%. Dissolution rates for apatite and halite, as a proxy for sylvite (KCl), are also given).
Table 5
Dissolution rate, log mol m
22
s
21
Mineral
Mineral family
Formula
Weight % K
Weight % K
2
O
Potassium feldspar
Feldspar
KAlSi
3
O
8
14.0
16.9
210.06
Leucite
Feldspathoid
KAlSi
2
O
6
17.9
21.6
26.00
Nepheline
Feldspathoid
(Na,K)AlSiO
4
8.3*
10.0
22.73
Muscovite
Mica
KAl
3
Si
3
O
10
(OH)
2
9.0
10.9
211.85
Biotite
Mica
K
2
Fe
6
Si
6
Al
2
O
20
(OH)
4
7.6
9.2
29.84
Phlogopite
Mica
K
2
Mg
6
Si
6
Al
2
O
20
(OH)
4
9.4
11.3
210.00*
Hydroxyapatite
Apatite
Ca
5
(PO4)
3
(OH)
n.a.
n.a.
24.29
Halite
Salt
NaCl
n.a.
n.a.
20.21
*
estimated
