Diamonds were first mined in India. Pliny may have mentioned them, although there is some debate as to the exact nature of the stone he referred to as Adamas; In 2005, Australia, Botswana, Russia and Canada ranked among the primary sources of gemstone diamond production.
The British crown jewels contain the Cullinan Diamond, part of the largest gem-quality rough diamond ever found (1905), at 3,106.75 carats (621.35 g).
Now popular in engagement rings, this usage dates back to the marriage of Maximilian I to Mary of Burgundy in 1477.
Metal finishes
For platinum, gold, and silver jewellery there are many techniques to create finishes. The most common are high-polish, satin/matte, brushed, and hammered. High-polished jewellery is by far the most common and gives the metal the highly-reflective and shiny look. Satin, or matte finish reduces the shine and reflection of the jewellery and is commonly used to accentuate gemstones such as diamonds. Brushed finishes give the jewellery a textured look, and are created by brushing a material (similar to sandpaper) against the metal, leaving 'brush strokes'. Hammered finishes are typically created by using a soft, rounded hammer and hammering the jewellery to give it a wavy texture.
Some jewellery is plated to give it a shiny, reflective look or to achieve a desired colour. Sterling silver jewellery may be plated with a thin layer of .999 fine silver (a process known as flashing) or may be plated with rhodium or gold. Base metal costume jewellery may also be plated with silver, gold, or rhodium for a more attractive finish.







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