Pakistani Indian Bridal Fashion Jewellery Collection 14

 Bridal Fashion Jewellery.

By Aamir Mannan.

THE SPECIFIC GRAVITY OF GEMSTONES AND HOW TO MEASURE IT

Every jeweller knows by experience that some gemstones 'weight heavier' than others; that, for instance, a white zercone weight more than a diamond of equal size and a sapphire more than an emerald.

Scientists long ago provided a precise definition for this quality of  'heaviness', which provides a valuable means of distinguishing one substance from another when worked out on a numerical basis.

This was done by taking water as a standard and comparing the weight of each substance with the weight of an equal volume of pure water. the figure thus arrived at is called the 'specific gravity' or 'relative destiny' of the substance of in question.

The specific gravity of a body, than, is simply the ratio of its weight to that of an equal volume of pure water. for accurate work, water 4 C is specified as the standard.

Thus, when we say the specific gravity of aluminium is 2.7 and that of ruby 4.0, we means that, bulk for bulk, aluminium weighs 2.7 times, and ruby 4 times, as much as water.

Materials used in jewellery show a very wide range in specific gravity, from amber, I.08, to platinum, 2I.5.