Cadmium prices treble on demand

Prices of cadmium, a metal used mainly as a hardening agent in alloys, almost trebled in the last 15 months due to rising demand from consumer industries. Hindustan Zinc, the country's largest producer, currently quotes cadmium of 99.5 per cent purity at Rs 478 a kg compared with Rs 174 a kg last February.

Global cadmium prices have also moved at a brisk pace and are currently quoting at $4.25 a pound compared with $3.25-3.30 a pound in the same period. Hindustan Zinc produces about 400 tonnes of pure cadmium and sells a chunk to the overseas market, mainly to China. The other primary and secondary zinc producers, including Binani Zinc, manufacture about 50 tonnes of the pure metal.

The global cadmium production this year is estimated at around 20,000 tonnes, of which China and Japan contribute about 15 per cent each, while South Korea, Canada and Mexico contribute about 13 per cent, 10 per cent and 9 per cent, respectively, with the balance coming from the rest of the world.

Almost 78 per cent of the world's cadmium is used mainly for manufacturing batteries, while use in pigments accounts for 11 per cent, 7 per cent in coatings, and 2 per cent each in stabilisers and alloys.

Of late, the demand for cadmium has grown manifold, with increasing demand from consumer industries such as metal toys, metal coating and dyes and pigments.

The metal and its compounds are used for electroplating of other metals such as steel, iron and copper and employed in alloys with copper, nickel, gold, silver and aluminium for coating other materials.

The metal compounds are also used in the production of pigments and dyes, as stabilisers in plastics, in welding, soldering and in electrodes of nickel-cadmium batteries.

The metal also finds application in printing, textiles, photography, lasers, semiconductors, solar cells, scintillation counters, dental amalgams, fluorescent lamps and super-phosphate fertilisers and pesticides. Like zinc, cadmium can be electroplated to other materials to protect them from corrosion.