1. Mineral Resources
2. Online Spatial Data
3. National Mineral Resource Assessment 1998

Mineral assessment tracts in Butte county, California

[Additional scientific data in this geographic area]

PC03: Skarn Cu (18b) (Mesozoic) , covers 71 % of this area

90%	50%	10%	5%	1%
0	0	0	0	1

PC08: Porphyry Cu (17) (Mesozoic) , covers 71 % of this area

90%	50%	10%	5%	1%
0	0	0	1	1

PC17: Massive sulfide, Sierran kuroko (28a.1) (Jurassic) , covers 4 % of this area

90%	50%	10%	5%	1%
2	13	25	25	25

PC26: Epithermal vein, quartz-adularia (25c + 25d) (Tertiary) , covers 26 % of this area

90%	50%	10%	5%	1%
0	1	2	2	2

PC28: Hot-spring Au-Ag (25a) (Tertiary) , covers 26 % of this area

90%	50%	10%	5%	1%
0	1	3	5	7

PC34: Hot-spring Au-Ag (25a) (Tertiary) , covers 10 % of this area

90%	50%	10%	5%	1%
1	1	2	2	2

PC40: Low-sulfide Au-quartz vein (36a) (Mesozoic) , covers 65 % of this area

90%	50%	10%	5%	1%
2	6	9	12	15