Fireclay

Definition and stakes

Alfred B. Searle,  The Natural History of Clay

“ Providing a clay has a sufficiently long vitrification range, a suitable colour when burned, and that it is capable of being readily formed into the desired shapes, its composition and origin are of small importance to the stoneware manufacturer. In actual practice, however, the number of sources of good stoneware clay is distinctly limited, and many manufacturers are thus compelled to add suitable fluxes to refractory clays [116] in order to meet some of their customers' requirements. For this purpose a mixture of fireclay with finely powdered felspar or Cornish stone is used. ”
Source: Gutenberg

1911 Encyclopædia Britannica, Volume 21… (1911)

“ The south-west extremity of the Edinburgh coalfield just enters this county over the north-west border where a slice of Carboniferous strata is found let down between Silurian and Old Red rocks by two important faults. Both Calciferous sandstone and Carboniferous limestone occur, with useful beds of coal, limestone, ironstone, fireclay and alum shale. An outlier of Carboniferous limestone, surrounded by Lower Old Red Sandstone, lies south of Linton. Much glacial boulder clay with gravel and sand rests upon the higher ground, while morainic deposits are found in the valleys. ”
Source: Wikisource

Portrait of Christian Sparre Christian Sparre,  The Black Tortoise: Being the Strange Story of Old Frick's Diamond

“ A strong blow in the centre of the circle—and to our great astonishment the round steel dial disappeared into the box.
"Well, hang it all!" shouted old Frick; "but how in all the world—?"
"It is simple enough, but none the less ingeniously done," answered Monk, dryly. "Mr. Howell couldn't manage the lock, and so he bored a number of small holes in one of the spirals, and afterward, with a watch-saw, he sawed through the space between them. He has shown himself to be a clever craftsman—that can't be denied.
”
Source: Gutenberg

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