測試方法 - Fineness Testing
I. 火試金法 - 灰吹法 Fire Assay - Cupellation
火試金法是經典的破壞性黃金成色測試方法，直接測定黃金含量
Fire assay is the classic destructive gold fineness testing method that directly determines gold content.
ISO 11426*
GBT 9288*
ASTM 1335
(*issue HOKLAS endorsed report)
1. 取樣稱重 Weigh Sample
2. 氧化灰吹 Cupellation
3. 貴金屬珠軋成薄片並卷成小卷
Flatten the bead & roll into cornet
4. 分金 Parting
5. 烘乾及稱重 Anneal & weigh cornet
II.減差法 - Difference Method by ICP
ICP減差法是另一種成色測試方法，以非直接的方法測定成色。樣本以王水溶解，用ICP-OES光譜儀測得雜質元素含量，通過減差總雜質量得出黃金含量。
ICP by Difference Method is a destructive, indirect fineness determination method. The alloys samples are weighed and dissolved in aqua regia. The impurities are determined by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Fineness content is obtained by subtraction of the total content of impurities in the sample.
1. 取樣稱重 Weigh Sample
2. 準備溶液 Prepare Solutions
3. ICP 測試 Analyze by ICP-OES