Hii Virat!
Swarn sankhya is called Gold number in English and is related to chemistry. The minimum amount of protective colloid in mg which prevents colour change from red to violet of 10 ml gold sol by addition of 1 ml of 10 % NaCl solution is called gold number. Examples- Gelatin- 0.005-0.01; heamoglobin- 0.03-0.07 etc.,
Hope this helps.
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