I saw some really cheap silver nitrate on ebay.

http://www.ebay.com/itm/ws/eBayISAPI...:B:WNA:US:1123

Is this useful for alt processes like salt prints?

Or do I have to buy the more expensive ACS grade?

http://www.ebay.com/itm/Silver-Nitra...efaultDomain_0

I don't need a whole pound, but what's the difference?

Thanks in advance!