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Boraq 2

Plainsman Plastic Gerstley Borate Substitute

Oxide Weight122.87
Formula Weight166.94
If this formula is not unified correctly please contact us.

Boraq 2 is a Gerstley Borate substitute that was made by Plainsman Clays. It was derived from Boraq 1 in response to these issues:

-The boron levels in Boraq 1 were deliberately higher than Gerstley Borate so that it would melt as well at low temperatures (GB has tramp minerals that no material made from more pure minerals will have). That meant that Boraq 1 was melting too much at cone 6.

-The MgO in Boraq 1 was also lower than GB (it contains very fine MgO-rich clay particles that source the plasticity, the Hectalite addition in Boraq 1 was not sufficient to supply it all).

-Boraq 1 was not working well with iron reds at cone 6. It seemed evident that this was because of either the lack of CaO or the lack of limestone-like minerals that occur in Gerstley Borate.

Boraq 2 adds 8 dolomite and 8 calcium carbonate to Boraq 1. The dolomite supplies the needed MgO. Gerstley Borate is basically calcium-borate, so adding the calcium carbonate dilutes the boron.

The chemistry of Boraq 2, Boraq vs Gerstley Borate (mole%):
Boraq 2 Boraq 1 GB
CaO 34.7 29.1 30.4
MgO 8.0 5.4 7.6
KNaO 4.6 4.8 5.7
B2O3 34.3 38.9 33.8
Al2O3 1.6 1.8 0.9
SiO2 17.2 19.5 21.6

While no longer manufactured, the process by which it was developed is over interest to technicians.

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In Bound Links

By Tony Hansen

XML for Import into INSIGHT

<?xml version="1.0" encoding="UTF-8"?> <material name="Boraq 2" descrip="Plainsman Plastic Gerstley Borate Substitute" searchkey="" loi="0.00" casnumber="167077-83-0"> <oxides> <oxide symbol="CaO" name="Calcium Oxide, Calcia" status="" percent="25.400" tolerance=""/> <oxide symbol="MgO" name="Magnesium Oxide, Magnesia" status="" percent="3.600" tolerance=""/> <oxide symbol="K2O" name="Potassium Oxide" status="" percent="0.500" tolerance=""/> <oxide symbol="Na2O" name="Sodium Oxide, Soda" status="" percent="3.200" tolerance=""/> <oxide symbol="Al2O3" name="Aluminum Oxide, Alumina" status="" percent="2.400" tolerance=""/> <oxide symbol="B2O3" name="Boric Oxide" status="" percent="26.500" tolerance=""/> <oxide symbol="SiO2" name="Silicon Dioxide, Silica" status="" percent="11.900" tolerance=""/> <oxide symbol="Fe2O3" name="Iron Oxide, Ferric Oxide" status="" percent="0.100" tolerance=""/> </oxides> <volatiles> <volatile symbol="LOI" name="Loss on Ignition" percent="26.400" tolerance=""/> </volatiles> </material>

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