| 摘要 |
<p>The stone body is formed of concrete comprising cement and sand which is 98.50% silicious. Specifically a coloured covering is obtained by mixing a hard superwhite cement mortar, containing 50-60% sand with a 98.50% silicious concentration and polyvinyl acetate (opt. contg. 3% copolymerised cpds.) and a synthetic pigment.</p> |
