Anyone using Arizona Rock & Mineral Ballast? I used some for my yard because I liked the color of the blend. HO Fine #1222 Yard Mix. After it was half glued down I realized the stuff contains metal. DOH! In fact about 90% of it jumps to a magnet. I'm concerned about it messing up my engines. Who else has used this stuff and have you had problems? See also "Metal in Ballast" in the Technical forum.