On later days they talked of the quarries in which Carter said he was going to work. There were many of them, for all the city of Inquanok was builded of onyx, whilst great polished blocks of it were traded in Rinar, Ogrothan, and Celephaïs and at home with the merchants of Thraa, Ilarnek, and Kadatheron, for the beautiful wares of those fabulous ports. And far to the north, almost in the cold desert whose existence the men of Inquanok did not care to admit, there was an unused quarry greater than all the rest; from which had been hewn in forgotten times such prodigious lumps and blocks that the sight of their chiselled vacancies struck terror to all who beheld. Who had mined those incredible blocks, and whither they had been transported, no man might say; but it was thought best not to trouble that quarry, around which such inhuman memories might conceivably cling. So it was left all alone in the twilight, with only the raven and the rumoured Shantak-bird to brood on its immensities. When Carter heard of this quarry he was moved to deep thought, for he knew from old tales that the Great Ones' castle atop unknown Kadath is of onyx.