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
The Malachite Casket (fairy tale) forgets about his mistress. He buys the Casket from her and offers it to Tanyushka, but she refuses. Turchaninov then claims that he wishes to marry the girl. She announces that she will only agree to the marriage if he shows her the Tsarina herself at the Malachite Room in Saint Petersburg. Turchaninov agrees. Dressed like a queen, Tanyushka arrives at the Palace, and walks directly to the Malachite Room. Tsarina enters the room, saying: "Now then, show me this nigh-handed maid". Upon hearing that Tanyushka frowns and says to Turchaninov: "What does this mean? I told ye to show