% Lost when refining

[diegogt96]

Hello my name is Diego and I'm new to this community. My father and I recently acquired a mine so we are starting to sell pure gold. Im struggling with understanding the weight that is lost when refining the gold from 20k to 24k. Does it vary or is there an specific formula for it?
Thanks in advanced

with regards

Diego Gomez

 

[g_axelsson]

That's an easy one, 20/24 parts is gold so 4/24 parts is the contaminant and is lost during refining.

But then you can have melt losses too, moisture, organic substances, pieces of minerals, iron oxides and so on. So unless you are melting bars and sends pure metal to the refiner you could have larger losses in weight than just 4/24 or about 16.5%.

Göran

 

[goldsilverpro]

Hello my name is Diego and I'm new to this community. My father and I recently acquired a mine so we are starting to sell pure gold. Im struggling with understanding the weight that is lost when refining the gold from 20k to 24k. Does it vary or is there an specific formula for it?
Thanks in advanced

with regards

Diego Gomez

Welcome, Diego. I assume this is placer gold. The impurities (the other 4K) are mainly silver and copper. The weight difference after refining is, of course, due to the loss of these impurities. However, if you're asking how much of a gold weight loss is permissible from the refining process, I would first ask what method you are using, in detail, to determine the percentage of gold in the un-refined material. It's impossible to determine your refining losses if you don't know, exactly, what is in your starting material. I hope you'll say that fire assay is being used. I hope that you're not relying on XRF.