The following chart shows what base skill is needed to mine that type of ore. Keep in mind that on this particular chart, numbers were taken from a new Sphere Server and not from flint hills.
Ingot Name
Minimum % needed to mine this
Ammount of ore per tile
Chance of mining ore as a GM
% of your ingots that will be this as a GM *
Iron
0%
9-30
47%
61.3%
Rusty
50.0%
8-21
6%
5.8%
Old Copper
60.0%
7-18
6%
5%
Dull Copper
65.0%
5-25
6%
6%
Shadow
70.0%
5-46
5%
8.9%
Copper
75.0%
5-20
5%
4.2%
Bronze
80.0%
4-12
4.5%
2.4%
Golden
85.0%
3-10
3%
1.3%
Rose
87.0%
3-9
3.5%
1.4%
Agapite
90.9%
3-8
3%
1.1%
Blood Rock
93.0%
3-6
2.5%
.8%
Silver
95.0%
1-2
3%
3%
Verite
95.0%
2-6
2%
.8%
Valorite
99.0%
2-4
1.5%
.4%
Mytheryl
99.5%
2-3
1%
.25%
Black Rock
100.0%
1-3
1%
.13%
*Exclude ingots gained before becoming a GM Miner.