On 7/18/2017 1:14 AM, Donalyn wrote:
replying to gobofraggle, Donalyn wrote:
Did you get an answer or find a solution

He did. The acid in gerbil urine will lighten the color. He lt loose a
herd of hundreds of gerbils and after six moths of letting them loose,
he was happy with the color of the floor. The residual odor is starting
to lighten up too.

The pyramids were built with onyx but look how they lightened up after
years of pigeon crap on them. Works