CALCULATING THE APPROXIMATE WEIGHT OF GOLD IN QUARTZ REEF ROCK.
I. Dry weight of the quartz and gold specimen =[A]
II. Weight of the displaced water =[B]
III. s.g.[specific gravity] of quartz = 2.65
IV. Weight of the displaced water x the s.g. =[C] assumed weight of the specimen if it was 100% quartz
V. A – C = approx. weight of the gold in the specimen
- Tare [zero] your scales, weigh the DRY, clean specimen rock [record this = A]
- Put sufficient water in a container [glass, or clear plastic] that would cover the rock. …. Or use a fancy graduated laboratory beaker.
- Use a permanent thin line marker on the outside of the container to mark the water level.
- Put the specimen in the water
- Mark the new water level on the container where the water level is displaced to
- Take the specimen out of the water, and let as much water drip off the specimen back into the water container as this can make a significant result to your calculation.
- Put the container of water on your sales and THEN TARE the scales [check the readout of the scales reads 0.00]
- Now add water up to the marked displacement line.
- Record the weight of the water [ the weight of the displaced water = B]
- Calculate: C = (B x 2.65)
- Calculate A – C = approximate weight of gold in the specimen.
The calculation becomes less accurate with the mass of other materials in a specimen. The only true measure is by dollying the rock.