The Malachite Box nuggets. The story of the brothers is continued in "The Snake Trail" (alternative translation: "The Serpent's Trail"), published in 1939. In this "skaz", a young the factory worker Stepan meets the legendary Mistress of the Copper Mountain. He passes her tests and is rewarded by a malachite casket filled with jewellery for his betrothed, Nastyona. Stepan dies, leaving the Malachite Casket to his widow Nastyona. Their daughter Tanyushka likes to play with it. With black hair and green eyes, Tanyushka does not look like her mother at all, as if she was born to different parents. When she grows up,
Mineral petrography), it may become transparent even if that property is not seen in a hand sample. In contrast, some minerals, such as hematite or pyrite, are opaque even in thin-section. Colour is the most obvious property of a mineral, but it is often non-diagnostic. It is caused by electromagnetic radiation interacting with electrons (except in the case of incandescence, which does not apply to minerals). Two broad classes of elements (idiochromatic and allochromatic) are defined with regards to their contribution to a mineral's colour: Idiochromatic elements are essential to a mineral's composition; their contribution to a mineral's colour is diagnostic.