Thread by @NeilRingdahl

1/15 THREAD: Gold metal accounting, East Katanga -DRC- style

Hats off to these guys.

UG Mining using hand implements. Head grade 3-5 g/t Mining recovery 40%. -> 7.5t moved for 1 tonne of ore. Mining dilution 0% -> Hand pick the ore.

2/15
Look at this workmanship! This particular hole was 36m deep & consisted of about 30 x 1.2m high steps. At the bottom, they rat hole in all directions along the structure. Scary stuff geotechnically, but they're way better than most trained geologists at finding pay shoots.

3/15 Its dangerous work, especially in the rainy season when these hole often collapse. Many die each year, but what else can a man in E. Katanga do? They are men of faith and they work for a "point" per day (0.1g/day or about $4 at today's price).

4/15 I caught these miners going home after a week of working, day & night. They work typically 14-18 hrs each day and snatch sleep under plastic or grass lean-to's, cooking for themselves. Saving money for batteries and beer. Really good men. Very humbling, their happiness.

5/15 We had it good, sleeping in the Catholic monastery each night after a three hour drive, the oldest brick building in the DRC, built by monks in 1935. They had the most amazing choir I have ever heard, which woke us during practice at 5:15 a.m. each day.
But I digress.

6/15 Back in the mining area, ore is carted in 40kg hessian bags on bicycles to milling stations. Here crushing takes place, again by hand.
Estimated losses to fines 5-10%
3g/t -> 2.7g/t

7/15 Crushing is also done by hammer. Note how worn the hammer in his hand is. This man earns US$0.50/day doing this. Its enough for one meal of Cassava. Grim. All-in mining & processing cost is about $20/tonne + a lot of sweat, blood & tears.

8/15 Milling with mercury added. Notice the mill ball behind the guy. His engine was broken that day, but he told us he normally mills about 3t/day. Its a 24 hr operation and he has 5 guys helping him. He is the boss man because he had money for an engine. And fuel. Its $4/litre.

9/15 Have a look at this mill shell & bearing. It gives new meaning to white-metal bearings 😏, but it works! Milling is a batch process. Load the mill by hand. Run it for a few hours &then unload. Repeat until you run out of fuel, which comes only by bicycle, a journey of 1 day

10/15 The milled product is then thoroughly mixed with mercury by treading -as you would tread grapes- in these UN-blue plastic lined "tanks". Afterwards the mercury amalgam is concentrated by sluicing off lighter material (sorry no pics).

11/15 Here is the is an amalgam bead. About 50% pure gold. The mercury is vaporized in pots that are also used for cooking, in the grass huts in previous pictures. Overall recovery is around 60%. It was too valuable & they were too scared to show us the final product, which...

12/15 is ferried in small, hidden quantities on bicycles to town. Here, it is sold to local buyers with dishonest scales, for just $500/oz at the time (2016). Transport and TC/RC's are the given reasons. As is always the case, terms UNreasonable are sold as MOST reasonable.

13/15 Yet despite the theft, the poverty there is joy. How is this possible? They have nothing yet they have EVERYTHING. We could learn a thing or two here, with our 1st world problems, sulky, sullen faces and mobile phones more important than the other person in the room?

14/15 Here are two gold buyers. These guys really did not like or want to be photographed but I managed to sneak in a shot nevertheless while they were talking to my father. These guys make good money: Perhaps $100/month or more.

15/15 From here the gold goes by boat the 80km across Africa's longest & deepest lake, Lake Tanganyika to be sold to fat-cat Arab traders in Tanzania, who in 2016 were buying for around $7-900/oz, again on dishonest scales. They naturally do best of all, like all off-takers.

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