Mining for sapphires
A day at the mine in Sapphire, Queensland, Australia
Step one of mining for sapphires, Lou cuts a new hole about 7 foot deep to the floor, thats where we hit good stone. Lou is fairly excited as he is getting closer to an old tunnel dug before the flood cave in. This area had produced around 100-200 carats of sapphire per day for a couple of months and we were looking forward to getting back to this area eventually.
Now the dirt is looking very good, heavy black broken ironstone with white bits of clay and green rocks. The old timers say you are on the sapphire when your wash has salt pepper and chives – the black broken ironstone – white ash / clay – green floor/arsenic rocks (don’t put these in your mouth). So Lou has been hack hammering this morning to loosen the dirt, he shovels it into buckets and then winches them to the surface.
Since we are working away from the machine and open cutting this hole, it is easier to winch to the surface. The buckets are lined up, ready to be put through the machine.
Then tipped into the machines big bucket and lifted up into the hopper.
The machine is started and the processing of the sapphires begins, the sapphires are heavy and drop into a tray with the aid of flowing water they are jiggled up and down and the waste with no sapphire in it is moved on and carried off for waste.
After about an hour or two the machine is turned off and the tray with the sapphires in is emptied into a bucket, it is tipped into a stack of 3 sieves, big holes at the top med holes in the center and little holes at the bottom, then into the whilouby to be pumped up and down to centre the sapphire in the middle and to get the different sizes into each sieve.
Over to the sorting table
Tip out the big stone sieve first – the is one big blue one 23 carats, we have a waiting list for the local sapphire carver, Sue wants a sapphire to carve, this one is not quite good enough to facet so it is perfect for carving, a rare practice featured here on the gemfields.
In the middle tray this is where you will find good sized sapphire nearly all cutters weighing around 3 to 14 carats. In this particular batch we found eleven.
And in the fine tray there are the usual one carat small sapphires in all sorts of beautiful colours and zircons. These little ones are often sent to Thailand to be cut for shoulder stones, unless the cutter is keen enough to cut tiny stones.
All in all a very good days this haul total of 173 carats!