Lead deposits are widely scattered throughout the Colony. The lead is usually associated with silver as argentiferous galena. There are fair deposits to be found at Silver Mine Bay, Lead Mine Pass and Lin Ma Hang. The mines at Lin Ma Hang were easily the largest and most modern before the war began. They were forced to close down in 1940 when the Japanese sealed off deliveries to China. At one time they were producing roughly 250 tons of lead ore (concentrated) and 7,000 ounces of silver monthly. The Japanese opened the mine again during the occupation.
Iron is everywhere in evidence but the only deposit which so far has attracted a major commercial exploitation is the lenticular magnetite mass at Ma On Shan. Its produc- tion is regulated by its chief customer the Green Island Cement Company. Surface scratchings for ochre, a hydrated oxide of iron, are worked on and off. The ochre is used by small local paint companies.
Wolfram, which is loosely called tungsten, occurs in several places. It is mined officially and unofficially at Shing Mun, Castle Peak, Ho Chung and on Lantau Island. By far the largest workings are at Shing Mun where a European company has the lease. The Japanese kept up a steady production during the occupation. To-day there are a hundred or so miners from these mines, which are temporarily closed, panning for placer wolfram in the bed of the Shing Mun River. Their output is presumably sold on the local market.
Kaolin, not excluding the great reserves of building stones and the sand and gravel deposits, is certainly the most valuable of the proved deposits in the Colony both in quantity and quality. It occurs everywhere in varying degrees of purity ranging from the best ball clay to the coarser varieties. Of the many deposits now being worked, the pit at Cha Kwo Ling is the most valuable and productive. Much of the clay from this pit is exported to Japan but some is used locally in the ceramic industry. Elsewhere other deposits are mined for the various brick, face powder, tooth powder and rubber companies.
There are stone quarries sited all round the coast. The ornamental grey Hong Kong granite is most usually worked for building stone.
Sands and gravels are available in large quantities mainly from the raised beaches along the coasts.
During the year a few permits were issued, on a month. to month basis, to small family concerns wishing to mine. small amounts of ochres and clays.
A manuscript copy of the findings of the team of geologists, of the University of British Columbia, who, under
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