Jewellery and precious metals. Grading polished diamonds. Terminology, classification and test methods not-for-sale It helps by setting out

It helps by setting out those characteristics and manufacturing requirements that affect safety

Quality specifications for cold coiled compression springs

— a pushing out device and / or

— Type 25: Wheel relieved and recessed on one side and relieved on the other side

Isolation valves separate the actuation mechanism of a valve from the media being moved

Jewellery and precious metals. Grading polished diamonds. Terminology, classification and test methods not-for-sale It helps by setting out1 Scope This document specifies the terminology, classification and the methods that are used for the grading and description of single unmounted polished diamonds over 0,25 carat (ct). This document applies to natural, unmounted, polished diamonds. It is not to be used for fancy coloured diamonds, synthetic diamonds, treated diamonds (other than is allowed for in 7. 4), nor for assembled stones.