From Prospecting To Selling

Jim Clanin writes:

From prospecting to selling: The life of a gemstone
Conventional mining engineering handbooks and courses have traditionally overlooked mining for gemstones and mineral specimens as an industry. This is mostly due to the fact that in ore mining, blasting is the first step in crushing the rock for processing and extraction of the valuable elements. In gem mining, the rock must be gently taken apart to avoid damaging the material.

Gem and specimen mining are different to all other types of mining. In all the other mining sectors from gold and silver to sand and gravel to oil and gas, there are four phases of mining. The only phase that gem mining has in common with the others is the first phase.

The first phase is prospecting: before any deposit can be assessed and exploited it must be found.

Phase two is exploration: during this phase, the ore deposit is drilled, mapped and sampled to give its overall size, shape, position, value and complexity. The operator will know whether this deposit is going to be profitable one or if it is marginal and the operator should wait until the value of the product gets to the level that a profit can be made.

Phase three is the development phase of the ore deposit. This means excavating haulage tunnels, if it is an underground mine, removing the overburden in surface operations and erecting processing plants to handle and process the material economically.

Phase four is exploitation of the deposit. The ore is mined, removed and process in the processing plant to a saleable form. It is in this phase that the profit is made when the stone is sold on the market.

Sometimes the development and exploitation phases can be carried out concurrently. An example of this could be in sand and gravel operations where the area around the pit develops as the pit expands. But the deposit will have undergone extensive exploration to show it has the necessary quality of material to produce a profit when exploited.

In gem mining the miner explores a deposit while developing (with tunnels or a pit) the structure until he finds something to exploit. He must gently take apart the rock so not to damage the minerals any more than they might already be. The deposit may have outward signs that it may produce minerals or gemstones of value but after some exploration the miner may find nothing valuable.

Useful link:
www.gemstone.org