Rio Tinto | Minerals and Metals for the world

Chris Morrissey's AtoZ of metals and minerals
What have we got for M, N, O and P? Tales from the unexpected, from the Taj Mahal to the deep blue sea - via a novel by Sir Walter Scott.

M is for Malachite, a vivid green carbonate of copper that contains 57.5 per cent by weight of the metal. The name is said to come from the Greek for a green herb called mallow, which normally has purple flowers. Rather confusingly, the colour mauve gets its name from the same Greek word.

Its distinctive colour, often in intricate patterns of pale and dark green bands, makes malachite an easy mineral to recognize. It is quite soft - only 3.5 to 4 on the Moh Scale - and not particularly hard wearing. Even so, it has always been popular as a decorative stone. Inlaid into white marble, malachite from Turkestan is one of the many coloured stones that decorate the Taj Mahal. Masses of malachite from the Ural Mountains were used by the Russian craftsmen to panel the palaces of the czars , decorate their furnishings and create exquisite works of art.

Malachite burns with a green flame, giving oxides that can be converted to copper metal by incandescent charcoal. It is the basis of a primitive smelting process that was probably discovered by noticing globules of copper in the ashes of a wind whipped campfire. Copper was being deliberately smelted from malachite rich ores at Timna in Israel as long ago as 4000BC. Nowadays, direct smelting plays little part in making malachite give up its copper.

Malachite is very common in the weathered portions of copper deposits, especially when there is limestone in the vicinity.



Chris Morrissey's AtoZ of metals and minerals What have we got for M, N, O and P? Tales from the unexpected, from the Taj Mahal to the deep blue sea - via a novel by Sir Walter Scott. M is for Malachite, a vivid green carbonate of copper that contains 57.5 per cent by weight of the metal. The name is said to come from the Greek for a green herb called mallow, which normally has purple flowers. Rather confusingly, the colour mauve gets its name from the same Greek word. Its distinctive colour, often in intricate patterns of pale and dark green bands, makes malachite an easy mineral to recognize. It is quite soft - only 3.5 to 4 on the Moh Scale - and not particularly hard wearing. Even so, it has always been popular as a decorative stone. Inlaid into white marble, malachite from Turkestan is one of the many coloured stones that decorate the Taj Mahal. Masses of malachite from the Ural Mountains were used by the Russian craftsmen to panel the palaces of the czars , decorate their furnishings and create exquisite works of art. Malachite burns with a green flame, giving oxides that can be converted to copper metal by incandescent charcoal. It is the basis of a primitive smelting process that was probably discovered by noticing globules of copper in the ashes of a wind whipped campfire. Copper was being deliberately smelted from malachite rich ores at Timna in Israel as long ago as 4000BC. Nowadays, direct smelting plays little part in making malachite give up its copper. Malachite is very common in the weathered portions of copper deposits, especially when there is limestone in the vicinity.
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