5th December 2017 - Monomatapa and King Solomon's mines.
P. R. Siegfried.
Ancient Gold Mining in Africa
Gold mining has been taking place on the planet for about as long as people first were captivated by the flash and sun-filled glint of gold. Noteworthy of all metals, gold doesn’t rust but remains yellow-gold, shiny and untarnished in appearance. It is exceptionally heavy and has the ability to form large aggregates or nuggets which can be worked and beaten out to form golden foil, wire and plates. Although too soft for average wear and tear it is a surprisingly resilient metal and has always been valued as a form of wealth as well as thing of beauty.
It is difficult to know who or in which part of the world gold was first exploited. Although specularite and ochre mines have been dated back to 12 000 BP, and flint, chert and silex even older; gold was certainly considered hugely valuable and important in ancient Egyptian (5 000 BP) and South American (2 800 BP) cultures. Other parts of old Africa appear to have become gold producers and worshipers as a consequence of their lands being particularly well endowed with gold. The ancient kingdoms of Dahomey, Mali and Ghana were known from Etruscan times (2 500 BP), while the mines of Monomatapa and Maravia have long featured in the legends of eastern Africa. Accounts of Egyptian mining taking place along the Zambezi River have yet to be verified but a strong case is made and it is postulated that gold mines of southern and central Africa were the original source of the ancient legend of King Solomon’s Mines. Contrasting recorded gold mining techniques by ancient writers such as Diodorus Siculs it appears that little has changed since gold exploitation by the Egyptians.
Working in Africa today as a gold explorer allows one to see and observe just how primal today’s gold artisanal exploration as well as processing and recovery are. It is an illustration of techniques which harness the most basic force of nature – gravity - and allow, with human ingenuity, gold to be released from rock and recovered.
For a naturally occurring substance, it is considered that alluvial gold was far more common in ancient times than today, with significant early recovery of this material. These early deposits would be easily worked and could be easily processed and the gold recovered. As these deposits were progressively mined out, the discovery of gold in hard rock led to mining underground and below surface.
Artisanal gold mining in Africa has changed little in the last 8 000 years. Gravels are moved and sorted, or rock is broken down with use of fire, rock and iron, and the gold released. The various interventions are employed and are discussed in detail:
- In order to recover the gold the most basic tool is use of the gold pan. In gold mining a gold pan is commonly made of tin sheet, galvanised iron, plastic, rubber inner tube, or traditionally carved wood. The action of the pan is unique and involves technique, practice, patience and perseverance (Figure 1). Moving gravel to expose new concentrations of heavy minerals including gold is needed and often younger apprentices or woman of the family assist with the manual labour tasks.
- A sluice allows natural flow and turbulent action of water to allow the gold to be caught by means of fibres or corrugations. Sheep fleeces worked well – the origin of the ‘legendary’ golden fleece of the Argonauts, but whereas today astro turf, corduroy and hessian bags are used, not long ago coconut fibres (and sheep fleeces) formed an effective trap for the gold particles.
- Mining of hard rock is carried out by use of fire to heat the rock over a couples of hours and then water is thrown on to quickly cool and shatter the rock allowing it to be recovered easily as small broken pieces. If auriferous these are ground and milled and then panned to recover the gold.
- Milling and grinding is carried out largely by woman using either stone grinding stone (Figure 2) or in some places inverted cones in the rock.
- Mercury may be used in places. Although gold melts at about 1050 oC it also forms an amalgam with mercury at room temperature. An amalgam is a mixture of two metals and in this case the mercury absorbs very fine gold which may be lost to the waste, and can later be boiled off on a stove or gas flame leaving pure gold behind. The Lydians in the 4th century BC were the first to use mercury for recovering and later ‘diluting their gold and silver coins – in fact due to the variable amount of mercury which could be contained it was made illegal for Greeks to accept this money as legal tender.
King Solomon was looking for funds in 950 BC. Hefty dowries were to be paid for not only the world’s most renowned Queen – she of Sheba, but an amazingly large harem as well. Over 700 wives and many concubines he was reported to have had. In Kings it is noted that the lost city of Punt was a trading center that offered gold and spice to Egypt and Israel. This must have been part of the Red Sea network of trading towns such as Zeila, Bulahar and Berbera in Somalia. Similar trade centres are found along the Indian Ocean coast of Africa and include Lamu, Mombasa and Ilha da Mozambique. Although various locales have been suggested for King Solomon’s Mines (Ethiopia, Kenya, Aden and Yemen), passing reference to the Egyptians having established a gold mining colony in Mashonaland, inland from the mouth of the Zambezi River leads to the suggestion that it is in Tete Province of Mozambique where these mines were located. Mention of five treasure ships having departed Punt for Kosseir to bring the gold to Queen Hatshepsut in 4000 BCE suggests long standing trade routes, as does Kings where two years is mentioned as the expected time for the gold ships to return. What is true is that substantial gold was produced by the early Portuguese and Indians from Goa from this region.
Pete R. Siegfried is an exploration geologist with many years of experience prospecting in Africa and other continents primarily focused on mineral commodities used in the agricultural industry, but also for gold. Early gold prospecting and mining techniques have been of interest, and the use of archaeology as a means of targeting areas which may have been under explored in the past is a passion of the author. Today Pete lives in Monchique and spends time continuing these endeavours.