The Ancient Greeks believed that diamonds were splinters of stars fallen to earth. It was even said by some that they were the tears of the Gods. Another legend has it that there was an inaccessible valley in the Central Asia carpeted with diamonds. 'Guarded by birds of prey, from above, and by snakes of murderous gaze, on the ground.' However the truth is that the exact origin of diamonds is still something of a mystery, even to scientists and geologists.

All the factors are important, and none can be taken in isolation of the other: you could buy a D colour, flawless diamond, but if the cut is 'poor' then it will appear as dull and lifeless, just as, a well cut diamond, which is J as a colour and I2 Clarity will have its brilliance affected by the lower colour and very low clarity.

Old style jewellery is very fashionable. Estate jewellery – vintage – antique – period – retro - deco, these are some of the terms that set the mood. 
How important are such terms when it comes to valuation?

What the Terms Mean
 

Lead-glass is the latest additive to bargain-basement rubies. It masks a badly fractured stone, but the result is no match for high-quality ruby.

Rubies with lead-based glass filler began appearing on the market about two decades ago. But in the past few years, the trickle has turned to a flood.
 

This article explains several different methods of Jewellery Manufacture and examines the effect on a final appraised value, for these methods.