The third category is at first sight more random - wooden sticks, walls, pots, ingots, spindlewhorls.
Penang was the closest gateway for importing mining equipment and other provisions for the mines, and for the export of tin ingots.
Using the kirizukai method of cutting a silver ingot into smaller pieces, silver was a highly versatile precious metal that could easily function as small denomination coinage.
To-day, an unmanned machine, computer-controlled, can take a huge ingot and fashion it into complex shapes with precisions of a millionth of an inch.
Exports, under licence, of copper alloys in ingot form are restricted, by arrangement with the trade, to a quota based on exports in 1949.
I regret that no suitable productive use for this factory has yet been found beyond the production of steel ingots from the open hearth furnaces.
The light metal then goes to furnaces for smelting to secondary ingot for use in aluminium house parts and for other industrial purposes.
If one continues to reduce capacity much below 11 million ingot tonnes, the question mark over the industry rears its head.
