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Nytal Talc

Description: Hydrous Magnesium Calcium Silicate

Oxide Analysis Formula
CaO 8.42% 0.17
MgO 30.00% 0.83
Na2O 0.34% 0.01
Al2O3 0.31% -
SiO2 55.20% 1.02
Fe2O3 0.16% -
MnO 0.17% -
LOI 5.41%n/a
Oxide Weight 105.11
Formula Weight 111.12


No longer available.

New York talc was mined around Gouverneur, New York since 1870. The area around the town is very rich in minerals, especially talc, a wide range of talcs can be found within a small area. Amazingly the material is no longer available (it has been plagued by controversy about whether or not it contains asbestos and whether the talc itself is the fibrous type (like asbestos) rather than platy type (like kaolin).

The RT Vanderbilt website recommends VanTalc (from Montana) as a substitute however its chemistry is quite different (it has almost no CaO (closer to theoretical which has zero CaO) and its iron content is much higher).

Nytal 99 and Ceramitalc HDT are pressing grades of talc for use in ceramic wall tile and artware. They have been standards in the ceramic industry for many years because of their white firing, reliability and wide deflocculation curve. They are "certifiable" for non-toxic purposes in an ever growing health conscious market. Both products develop high uniform thermal expansion and low moisture expansion to prevent crazing in bodies that can be safely fired at rapid cycles. Nytal 99 produces bodies with somewhat lower shrinkage than Ceramitalc HDT, otherwise they are similar.

Nytal 100 is used as an auxiliary flux in vitreous bodies such as electrical porcelain and sanitaryware. Recommended for cordierite development in refractory specialties, and to impart strength and resistance to delayed crazing in semivitreous dinnerware. Nytal 100HR and Ceramitalc 10AC have special use in art pottery and hobby casting slips. All three grades perform well in dry pressing, ram-pressing and in the making of good casting slips.

Nytal is offered in various particle sizes. White talcs are usually thought of as soft materials, but this contains an appreciable amount of other silicate minerals which can be somewhat abrasive.

Density Mg/m3 2.85
pH at 10% solids 9.4

Abrasiveness (Einlehner M/M2 loss, 174,000 revolutions) 175-300

Related Information


Materials Talc
A source of MgO for ceramic glazes, a flux or thermal expansion additive in clay bodies, also used in the manufacture of cordierite.
Materials VanTalc
Hazards Talc Hazards Overview
Talc is invaluable in the ceramics industry, it is used as a glaze and body ingredient and as a parting a release agent in various processes. Is it safe?
Typecodes Flux Source
Materials that source Na2O, K2O, Li2O, CaO, MgO and other fluxes but are not feldspars or frits. Remember that materials can be flux sources but also perform many other roles. For example, talc is a flux in high temperature glazes, but a matting agent in low temperatures ones. It can also be a flux, a filler and an expansion increaser in bodies.
By Tony Hansen
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