Mineral Examples of such minerals are malachite (green) and azurite (blue). In contrast, allochromatic elements in minerals are present in trace amounts as impurities. An example of such a mineral would be the ruby and sapphire varieties of the mineral corundum. The colours of pseudochromatic minerals are the result of interference of light waves. Examples include labradorite and bornite. In addition to simple body colour, minerals can have various other distinctive optical properties, such as play of colours, asterism, chatoyancy, iridescence, tarnish, and pleochroism. Several of these properties involve variability in colour. Play of colour, such as in opal, results in
Ruby, Gold and Malachite Ruby, Gold and Malachite Ruby, Gold and Malachite is an oil-on-canvas painting by Henry Scott Tuke. It depicts six young men in and around a boat, bathing in the sea. It was painted near Falmouth and exhibited at the Royal Academy summer exhibition in 1902, along with two other works by Tuke, "The Run Home" and "Portrait of Alfred de Pass". It was one of his greatest successes. The painting measures by . It was acquired by the City of London Corporation and is displayed at the Guildhall Art Gallery. Tuke was born in York in 1858, but his family