Joe's Model Trains Co.
Real Rocks Ballast - 8 Ounces

Limestone
Walthers Part # 350-123, p. 346 Walthers 2012 HO Scale Reference
HO scale, $12.95, currently in stock at Walthers

 
Imported quartz stone aggregate features uniform roundness and no excessive trash particulates. Prototypical color, size and weight. One ounce covers approximately one foot in HO Scale and two lineal feet in N Scale.