Joseph Aspdin's Portland Cement
From Rock
Quarrying for Cement Manufacture (1918)
In 1824, Joseph Aspdin, of Leeds,
England, received a British Patent [21 Oct 1824, No. 5022] for a product which he named
"Portland cement" because the set cement resembled the oolitic
limestone of Portland, England. The specifications for the new cement
were somewhat vague; a very pure limestone was to be burned to lime,
the lime mixed with a definite quantity of clay, and the mixture
pulverized wet. The wet mixture was to be dried and crushed and then
calcined in a vertical kiln and finally the calcine was to be powdered.
The patent does not state what proportions of lime and clay should be
used, nor at what temperature the mixture should be burned.
The manufacture of Portland cement
began in England and on the Continent shortly after the patent was
issued. However, at the time natural cement was widely used, and as it
could be manufactured more cheaply than Portland cement, the growth of
the latter industry was very slow.
Text from: Rock
Quarrying for Cement Manufacture, by Oliver Bowles, published by U.S. Dept
of the Interior as Bulletin 160 - Mineral Technology 22, page 4. (1918)
