•The secret to cool bodies and glazes is a lot of testing.
•The secret to know what to test is material and chemistry knowledge.
•The secret to learning from testing is documentation.
•The place to test, do the chemistry and document is an account at https://insight-live.com
•The place to get the knowledge is https://digitalfire.com

Sign-up at https://insight-live.com today.

Portland Cement

Oxide Weight83.09
Formula Weight85.83
If this formula is not unified correctly please contact us.

Manufactured using limestone and shale. Powder is mixed and fired in a rotary kiln to near-stoneware temperatures. The clinker is finely ground to produce a grey powder that reacts with water to form a hydrous calcium silicate with some CaO left over.

Acids do attack cement however as soluble materials are removed less reactive remaining materials are quite stable.

Richard Willis

A relatively high-temperature calcinated mix of clay and lime which hardens quickly after wetted with water and left to air-dry. Unlike most “natural” clay cements, however, Portland’s bonding deteriorates under time, stress and weathering. Like all clay cements, Portland, behaving as a calcined calcareous earth, will fuse readily when fluxed and will melt at much lower temperatures than its required high calcinating temperatures. A simple brown glaze, for example, can be obtained at 900º ;C from a thick solution comprising equal parts of Portland and hydroboracite or minium.
typical analyses of compositions, after calcinated at 1300-1500ºC
“limestone”; 52% lime, 3% silica, 1% slumina, 0.5% iron, 0.5% magnesia, 42% burned away
“chalk”; 54% lime, 1% silica, 0.5% alumina, 0.2% iron, 0.3% magnesia, 43% burned away
“cement rock”: 43% lime, 11% silica, 3% alumina, 1% iron, 2% magnesia, 36% burned away
“clay”: 1% lime, 57% silica, 16% alumina, 7% iron, 1% magnesia, 14% burned away
“slag”: 42% lime, 34% silica, 15% alumina, 1% iron, 4% magnesia, 0% burned away

By Tony Hansen

XML for Import into INSIGHT

<?xml version="1.0" encoding="UTF-8"?> <material name="Portland Cement" descrip="" searchkey="" loi="3.20" casnumber=""> <oxides> <oxide symbol="CaO" name="Calcium Oxide, Calcia" status="" percent="62.275" tolerance=""/> <oxide symbol="MgO" name="Magnesium Oxide, Magnesia" status="" percent="2.215" tolerance=""/> <oxide symbol="Al2O3" name="Aluminum Oxide, Alumina" status="" percent="7.549" tolerance=""/> <oxide symbol="SiO2" name="Silicon Dioxide, Silica" status="" percent="22.647" tolerance=""/> <oxide symbol="Fe2O3" name="Iron Oxide, Ferric Oxide" status="" percent="2.113" tolerance=""/> </oxides> <volatiles> <volatile symbol="LOI" name="Loss on Ignition" percent="3.200" tolerance=""/> </volatiles> </material>

Feedback, Suggestions

Your email address


Your Name


Copyright 2003, 2008, 2015 https://digitalfire.com, All Rights Reserved