“The proportions of our common glaze are as follows, together with every intermediate proportion, videlicet:—
| Growan gravel | 128 | parts | The materials ground and mixed together with water. |
| Growan or moor-stone | 112 | „ | |
| and I vary it from 96 to 144 | „ | ||
| Magnesia | 16 | „ | |
| and I vary it from 14 to 18 | „ | ||
| Gypsum | 3 | „ | |
| Lime | 8 | „ |
“But I also use the following materials for glaze:—
| Growan clay | 128 | parts | The materials ground and mixed together with water. |
| Growan or moor-stone | 112 | „ | |
| and I vary it from 84 to 140 | „ | ||
| Magnesia | 20 | „ | |
| and I vary it from 16 to 24 | „ | ||
| Lime | 8 | „ | |
| and I vary it from 6 to 10 | „ | ||
| Nitre | 1 | „ | |
| and I vary it to 2 | „ | ||
| Fusible spar | 20 | „ | |
| Arsenic | 20 | „ | |
| Lead and tin ashes | 20 | „ | |
| and I vary it from 16 to 24 | „ |
“I have described truly and justly the raw materials, the mixture and proportions of them which are used in making my porcelain, which has the appearance and properties of Dresden or Oriental porcelain, and which porcelain may be distinguished from the frit or false porcelain, and from the pottery, or earthen or stone wares, as follows:—
“The frit or false porcelain will all melt into a vitreous substance, and lose their form and original appearance in a degree of heat which my porcelain, agreeing in all properties with Asiatic and Dresden, will not only bear, but which is necessary for its perfection. My porcelain may be distinguished from all other wares which are vulgarly called earthen or stone wares, which can sustain an equal degree of heat, by the grain, the colour of the grain, and by its semi-transparency; whereas the earthenwares, such as Staffordshire white and yellow earthenwares and all other earthenwares which sustain a strong heat without being fused, are found, when subjected to the most intense heat, to appear cellular or otherwise, easily by the eye to be distinguished from the true porcelain.
“In witness whereof, I, the said Richard Champion, have hereunto set my hand and seal this twelfth day of September, in the year of our Lord one thousand seven hundred and seventy-five, and in the fifteenth year of the reign of our Sovereign Lord, George the Third, by the grace of God, of Great Britain, France, and Ireland, King, Defender of the Faith, and so forth.
“Rich. (S. S.) Champion.
“Sealed and delivered in the presence of us,
“Henry Sherwood,