Page 146 - Gillrath Edition IV - EN

KNOWLEDGE
CHARACTERISTICS
Steamed clinker bricks
The refined ring kiln clinker
Steamed bricks undergo an additional specialised manufacturing step.
Initially these bricks are fired in the ring-kiln in the traditional manner. Later the distinctive grey-black tonings are introduced through another process dur-
ing which oxygen is excluded.
Characteristics of our clinker bricks
None like the other
Part of the beauty of our bricks is that no two are identical. The colours that result from each ring kiln firing are due to natural fluctuations. No two firings pro- duce exactly the same results.
Most of our brick product ranges should be laid alternately (front and back). Small cracks, coal burnings and spalling are some of the char- acteristics of our coal-fire products.
These characteristics are a natural result of ring-kiln production and are not subject to complaint.
When the rustic and unique stones are sorted out of coal fire the assortments, the sorting loses its vitality.
The method in which the bricks are stacked in the kiln is largely responsible for the iridescent colour change in the fired clinkers.
The salt and coal mixture add- ed during a coal firing burns on the stone in the ring.
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