Franz,
Obviously you can calculate the cubic meters or yards (the volume), but to calculate tonnage, you have to know what the standard weight of a particluar ore is per cubic meter or yard, i.e., the density. I posted my calculations a while back in respnse to a post by MiningJunkie.
I used the desnsity of copper ore. You can get valuable information, such as the chart below, form this website. Regards, B.
http://www.mininglife.com/Miner/general/Density.htm
Material |
Specific Gravity |
Tons / Cubic Yard |
Andesite |
2.5 - 2.8 |
2.11 - 2.36 |
Basalt/Traprock |
2.8 - 3.0 |
2.36 - 2.53 |
Coal - Anthracite |
1.3 |
1.08 |
Coal - Bituminous |
1.1 - 1.4 |
0.92 - 1.18 |
Copper Ore |
2 |
1.89 |
Diabase |
2.6 - 3.0 |
2.19 - 2.53 |
Diorite |
2.8 - 3.0 |
2.36 - 2.53 |
Dolomite |
2.8 - 2.9 |
2.36 - 2.44 |
Earth (dry) |
1.6 - 1.8 |
1.35 - 1.52 |
Earth (wet) |
2 |
1.6875 |
Gneiss |
2.6 - 2.9 |
2.19 - 2.44 |
Granite |
2.6 - 2.7 |
2.19 - 2.28 |
Gypsum |
2.3 - 2.8 |
1.94 - 2.36 |
Iron Ore |
4.5 - 5.3 |
3.79 - 4.47 |
Lead Ore (Galena) |
7.5 |
6.21 |
Limestone |
2.3 - 2.7 |
1.94 - 2.28 |
Marble |
2.4 - 2.7 |
2.02 - 2.28 |
Mica, schist |
2.5 - 2.9 |
2.09 - 2.43 |
Quartzite |
2.6 - 2.8 |
2.19 - 2.36 |
Rhyolite |
2.4 - 2.6 |
2.02 - 2.19 |
Rock Salt |
2.5 - 2.6 |
2.11 - 2.19 |
Sandstone |
2.2 - 2.8 |
1.85 - 2.36 |
Shale |
2.4 - 2.8 |
2.02 - 2.36 |
Slate |
2.7 - 2.8 |
2.28 - 2.36 |
Talc |
2.6 - 2.8 |
2.19 - 2.36 |
Density (in lb/cu ft.) = SG X 62.4 |
Density (SI units) = SG X Density of water (1.0 g/cc or 1000 kg/cubic metre |