search  current discussion  categories  glazes - cone 4-7 

glaze test for marges clear, anthracite, c6, oxidation

updated sat 23 dec 00


Wade Blocker on thu 21 dec 00

Dear Alisa,
Anthracite is black natural coal. Therefore the anthracite title means
that the result is probably black like coal. Mia in sunny ABQ

Alisa and Claus Clausen on thu 21 dec 00

Anthracite, C6 oxidation.
Source: Chirs Clarke
Tested on mid range, iron flecked stoneware, cone 6, oxidation.

Receipe for base glaze

17 Whiting
35 spar
12 Ball clay
19 Silica
17 Zinc ox.
5 Rutile, 10 R.I.O, 1 Cob.

Resulted in very dark, smooth brown black semi gloss. Even in color, no =
discernable difference where dipped once or twice.

Personal: I was curious what Anthracite means?! Is that a name for =
this type of color? It is almost tenomoku like in brown to=20
black nuance.
Best regards,
Alisa in Denmark

patrick conrey on thu 21 dec 00

Anthracite is a type of coal mined in eastern Pennsylvania! It is also
called "hard" coal. It is used primarily as a heating fuel for home use.
It used to be mined by the deep tunneling method because the veins were
relatively deep in the ground down over 100 feet.

The mining of this mineral in the late part of the 19th century and early
part of the 20th century created many social and economic problems, for
example, my grandfather started working in the mines at age 10. He told
me that he worked from 6 AM to 6 PM, six days a week. In winter, he only
saw the sun on Sundays!

The demand for this type of coal deminished, after World War II, when the
returning GI's converted home heating to gas or oil. It is still mined
and used but only on a limited basis and is primarily mined by stripping!
In Pennsylvania, they referred to it as King Coal"