Sakura Red stone naturally contains iron salts and calcium compounds in cement that seep through the capillary pipes to the surface when acted upon by water, causing various "diseases." Waterproofing and anti-staining treatments are required. Additionally, polished stone surfaces become slippery when wet, with the coefficient of friction potentially as low as 0.2 on damp stone surfaces. Walking on such unhandled, wet stone floors is unsafe, and anti-slip treatments are necessary.