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Silver Gallon

Kirk Keyes

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Jun 17, 2004
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OK - I enjoy funky units, as long as I don't have to use them. So I have to ask, what's a "Silver Gallon"?
 
Didn't your source explain it Kirk?

At Kodak, we used a measure called a silver gallon. I never used it myself, but it was a funky measure of silver content in a raw melted emulsion. I myself used a more standard unit Kg of melt / mole of silver.

PE
 
Well, I thought I would just toss that out there for whoever wanted to have fun with it.

I see my Duffin book often uses "ripening volume" in ml melt/mole Ag. Probably very similar to your kg/mole Ag. Just the density difference between them.
 
We found that due to variations, the only exact measure was to do an analysis of the emulsion to determine the silver content. However, Kg / mole eliminated the density variations inherent in volumetric measure.

In any case, we developed a series of density equations for most everything including mixtures and temperature effects. This model helped us convert units handily to better than 0.01% from 20 - 40 deg C with things as diverse as NaBr/KI mixtures and AgNO3 up to 4 molar. It also included models for AgX.

Ammonium Hydroxide, with a negative density profile was one of the more difficult as were many volatiles.

PE
 

Is that something Kodak published, or could we get them to publish? It would be nice to have...
 
It's the volume of silver a person can carry walking at a speed of 1 furlong/fortnight.
 
Is a UK silver gallon larger than a US silver gallon?
 
Is that something Kodak published, or could we get them to publish? It would be nice to have...

The equations are extremely complex. I was a member of the KP density standards committee that tested and verified the algorithms that did the calculations.

I doubt if they would be interested in publication. In fact, you would need a rather complex computer program to implement the entire series of calculations.

As for the US and Imperial silver gallon, , IDK if one ever existed. I never had to work with it. I worked with Kg/M.

PE