SHOW: Rings 143
Title: Ring. General: 18K Gold ring set with a Natural Pearl. Material: 18K Gold. Gem: Natural Pearl. Method: Constructed, Flame Textured edges. Finish: Polished. Mechanics: Pegged and Glued. Designer: W.van Heeckeren. Craftsman: W.van Heeckeren. Price: AUS $ 5800.00.
18K GOLD is a ternary Gold alloy consisting of: 750 parts/1000 Pure Gold. 125 parts/1000 Pure Silver. 125 parts/1000 Pure Copper. Annealing temperature: 750 degrees Celsius. Melting Temperature: 950 degrees Celsius. Wal.
Flame Thickening is done by heating the edge of the metal with a very hot flame until the edge at the flame melts. The cohesion and surface tension of the moulten metal form the edge into a smooth thickened area. Wal.
name: PEARL colour: Pink, silver, cream, golden, green, blue, black colour of streak: White mohs hardness: 3-4 specific gravity: 2.60-2.78 cleavage: None fracture: Concoidal or scaly crystal system: Microcrystalline chemical composition: 84-92% calcium-carbonate, 4-13% organic substances, transparency: Translucent to opaque refractive index: 1.52-1.66 Black: 1.53-1.69 double refraction: Weak or none dispersion: None pleochroism: None absorption spectrum: Not usable fluorescence: Weak; not usable. Natural black: red-reddish