![](https://coimages.sciencemuseumgroup.org.uk/510/927/large_thumbnail_smg00294910.jpg)
Boxed bottle of "Bio-trey" silicate cement powder
1975-1980
1975-1980
1975-1980
1930-1960
1925-1940
1920-1940
1920-1940
1930-1945
1920-1940
1930-1940
1925-1930
1970-1976
1965-1975
1973-1976
1920-1940
1920-1935
1925-1940
1975-1980
1970-1980
1975-1980
1930-1960