Kyanite or Disthene is a translucent pale to sapphire blue mineral. The name Kyanite is derived from the Greek word “kyanos” which means deep blue, while the name Disthene is derived from its anisotropism, i.e. its property of exhibiting variable hardness depending on its orientation. Its hardness varies from 4.5 to 7 in the Mohs scale, depending on the direction it is processed.
Onyx is a variety of agate, which is a variety of chalcedony, which is a variety of quartz. Onyx is encountered in white, black and beige-brown. Its name is of Greek origin and refers to the lines that can be seen on the claws of several animals. It is considered to give courage to overcome difficulties and encourage decision-making. This mineral is also mentioned in Theophrastus’ work. In the bible, it represents Benjamin, the twelfth tribe of Israel.