granite

12

micaschist

4

amphibolite

3

marble

3

serpentine

3

coal

2

gabbro

2

Gneiss

2

jasper

2

obsidian

2

quartzite

2

sandstone

2

schist

2

slate, flaggy

2

almandine-micaschist

1

basalt

1

conglomerate

1

dolomite & calcite

1

Garnet-gneiss

1

Iron, Specular

1

ironstone

1

kyanite-garnet-schist

1

lava

1

limestone

1

limestone, shelly

1

ore, copper

1

ore, copper & iron

1

pegmatite

1

phyllite

1

quartz

1

sandstone, flexible

1

serpentinite

1

slag

1

slate

1

staurolite-mica-schist

1