Search results
Results from the WOW.Com Content Network
Analyzing gold using XRF spectrometers gives the purity of gold, up to 10-12 microns and hence it gives the analysis of coating only. Using this technique, the precise percentage or karat (of karat ) in a solid piece of jewelry can be determined in 30 seconds.
Diamond reports from GIA (as well as other, for-profit sources) are now demanded by most consumers purchasing diamonds over a certain size, typically for over 0.5 carat (100 mg), and almost always for over 1.0 carat (200 mg), and are considered an important tool in guaranteeing that a diamond is accurately represented to a potential buyer.
A model of a late 19th-century Canadian seal used to certify the quality of assayed gold. A metallurgical assay is a compositional analysis of an ore, metal, or alloy, usually performed in order to test for purity or quality. Some assay methods are suitable for raw materials; others are more appropriate for finished goods.
Carob seeds have been used throughout history to measure jewelry, because it was believed that there was little variance in their mass distribution. [10] However, this was a factual inaccuracy, as their mass varies about as much as seeds of other species. [11] In the past, each country had its own carat. It was often used for weighing gold.
Carat is a weight measurement used for gems. Karat is a measure of purity used for metals (most common is gold.) As far as the measure of purity is concerned the system is based upon a total of 24 parts i.e. 24K gold is pure gold, 18K is 18parts gold 6 parts other metals (which form an alloy) and so on.... 20:45, 18 September 2007 (UTC)
Diamond clarity is the quality of diamonds that relates to the existence and visual appearance of internal characteristics of a diamond called inclusions, and surface defects, called blemishes. Clarity is one of the four Cs of diamond grading, the others being carat , color , and cut .
It is an extension of the older karat system of denoting the purity of gold by fractions of 24, such as "18 karat" for an alloy with 75% (18 parts per 24) pure gold by mass. The millesimal fineness is usually rounded to a three figure number, particularly where used as a hallmark , and the fineness may vary slightly from the traditional ...
Certified reference materials (CRMs) are 'controls' or standards used to check the quality and metrological traceability of products, to validate analytical measurement methods, or for the calibration of instruments. [1] A certified reference material is a particular form of measurement standard.