20/30406119 DC:2020
20/30406119 DC:2020
BS ISO 24016. Jewellery and precious metals. Grading polished diamonds. Terminology, classification test methods Part 1. Terminology
20/30384025 DC:2020
BS ISO 29991 ....
20/30406163 DC:2020
BS ISO/IEC ...
BS ISO 24016. Jewellery and precious metals. Grading polished diamonds. Terminology, classification test methods Part 1. Terminology