I would try mixing some ammonia with water. This will create Ammonium hydroxide
Frederick M. Hueston
www.stoneforensics.com 321 514 6845
-----Original Message-----
From: daci6537 <daci6537@comcast.net>
To: Stone and Tile PROS Technical Support <sccpartners@stoneandtilepros.com>
Sent: Mon, Mar 9, 2015 1:07 pm
Subject: cooper stair removal
Does anyone know how to get out cooper stains from stone? We have been trying to find Ammonia Oxide. but can not find anyone who sells it. Does anyone know where we maybe able to get a product with it in it? Thanks