Czech opal silver necklace

Czech opal silver necklace : this necklace is composed of a line-shaped plate in blackened silver. In the centre is a modernist design in gilded silver enclosing an opal cabochon. This noble opal is transparent with a range of colours from purple, through blue, green, orange and yellow. The silver chain is fine and made of fancy links. Czech jewel, Prague, circa 1960.  

Marked 925, FHA mark, Czech guarantee mark

Length: 43 cm
Dimensions of the main motif: 5,6 cm x 4,3 cm
Diameter of the opal: 4 mm

Note: the chain is adjustable with rings.

Weight : 8,08 gr

Gemmology and beliefs : There are several types of opal: the noble opals and the common opals. The noble opals, like this one, have a play of colours due to the light. It is composed of tiny siliceous spheres aligned and of the same diameter. When the light hits the stone, and depending on the angle from which it is viewed, the surface of the opal plays with light. The common opal does not have luminous games, these spherules are disordered, and of different diameters, the light will only give it a “milky” aspect. In the collective imagination, the opal would have the capacity to make invisible. Hence its designation as the patron saint of thieves in the late Middle Ages.