Powdered boric acid tends to clump up and float when added to water naking it difficult to dissolve. Jerry ________________________________ From: harry kalish <hksvk@xxxxxxxxxxx> To: pure-silver@xxxxxxxxxxxxx Sent: Wed, October 13, 2010 9:50:04 PM Subject: [pure-silver] Re: Citric Acid as stop bath Why does it need to be crystalline? Thanks, Harry On 10/13/10 2:06 PM, "Gerald Koch" <gerald.koch@xxxxxxx> wrote: Use crystalline boric acid rather than the powder >