250 
ttERAMIC STUDIO 
the many artisans who during late years have left Golfe 
Juan and Vallauris to practice their trade in Marseille, 
Paris, Aubusson, Limoges, etc. 
PREPARATION OP MATERIALS 
For several centuries the process for obtaining metal- 
lic deposits on the glaze was transmitted in Spain by tradi- 
tion only. But, in Italy, in 1548, a ceramic painter, Piccol- 
passo, wrote, giving a very exact description of the method 
in use in all Italian potteries. 1 
Besides this, in 1785, in answer to an official request 
the alcaid of the city of Manises, the great center of Hispano- 
Moresque ceramic fabrication, sent to Madrid the old Arabic 
recipe. The manuscript was published only in 1877 by 
Don Juan F. Riano. 2 
The following are the directions given by the alcaid 
Manuel Martinez de Frugo : 
"First firing— Biscuit. 
"Second firing — Glazing. 
"The pieces, after being made, fired and glazed with a 
stanniferous enamel, are submitted to a third firing to ob- 
tain the golden effect. 
"Five ingredients form the composition of the golden 
matter, these are : 
Copper, the older the better. 
Silver, about which the same remark may be made. 
Sulphur. 
Red ochre mixed with clay, called here almagra. 
Strong vinegar. 
"The mixture of these ingredients is made in the follow- 
ing proportions : Copper, 3 ounces; Silver, a small piece; 
Sulphur, 3 ounces; Ochre, 12 ounces; Vinegar, 1 azumbre 
(3* pints.) 
"To this mixture is added three pounds twelve ounces 
of the scoria which is scrubbed off the ware after the firing 
of the golden color, the ware being at that time washed in a 
basin full of water in which the scoria is deposited. 
"Here is how the combination of these ingredients is 
made: a little ground sulphur is placed in a metal spoon 
with two small pieces of copper and between them a small 
piece of silver; then it is covered with sulphur and copper. 
The spoon is placed on a fire and left there for a thorough 
combustion of the sulphur, which is completed when the 
flame naturally dies out. 
"When the material contained in the spoon has cooled 
off, it is carefully ground; then the ochre and scoria are 
thoroughly mixed by hand, and the whole is again ground 
to the consistency of a fine powder which is placed in a 
basin. Water is added so as to form a paste which will ad- 
here to the sides of the basin, and it is fixed there with a 
trowel, one being careful not to leave any paste at the bot- 
tom of the dish. Of course in order to obtain this result, 
the water must be added gradually until the paste is of 
the proper consistency. 
"After being thus prepared the basin is placed in the 
kiln during six hours, and in Manises this is done at the 
time of the first firing of the ware. The contents of the 
basin are scrubbed off with a piece of iron and crushed in a 
mortar, then placed in a hand mill with the vinegar which 
so far has not been used. The whole is ground during a 
1. C. Piccolpasso — Li trelibri dell'arte del Vasaio, 1548. Manuscript in the 
South Kensington Library. 
2. Don Juan F. Riano — Sobre la manera de fabricar la antiqua loza dorada 
de Manises, Madrid, 1877. This pamphlet cannot be found to-day but 
an English translation was published in 1879 by the South Kensington 
Museum. . I owe much useful information on this subject to Mr. L. Solon, 
of Stoke on Trent, whose ceramic library is one of the most complete in 
the world. (L. F.) 
couple of hours and the result is the golden color ready for 
the decoration of the ware (Valencia, February 18, 1785)." 
So far as the preparation of the golden color is con- 
cerned, the manuscript of Manuel Martinez de Frugo thus 
gives us very thorough instructions; but, although it men- 
tions the third firing, which is the reducing firing, it does 
not say how this firing was done. Fortunately this impor- 
tant information, as we will see later on, is found in the 
accounts of the Moresque manufacture established in 
Poitiers by the Duke of Berry. 
The manuscript published in 1548 by Piccolpasso, also 
gives, in addition to formulas, the method of firing which is 
required for the production of metallic deposits. This is 
worth considering, as the Italians had obtained the process 
from the Moors. The French translation of Piccolpasso's 
work by C. Popelyn being incomplete, I have consulted 
Passeri who in 1758 compiled from it a small treatise. 1 
Unfortunately this treatise is full of erroneous conclusions 
and discrimination must be used when consulting it. But 
Passeri gives the technical details without any of his strange 
comments, and we find the following formulas : 
a b 
Terre rouge 3 ounces 6 ounces 
Ferret d'Espagne. . 2 " 3 " 
Bol dArmenie . . . . 1 " 
Cinabre mineral 3 " 
Argent calcine" 1 " 
6 ounces 13 ounces 
"Terre rouge" is red ochre which was used mixed with 
"Bol dArmenie." a ferruginous clay. Passeri also men- 
tions red toccalapis which is hematite. "Ferret d'Espagne" 
is copper sulphide. "Argent calcine" (calcined silver) is 
undoubtedly silver sulphide which was obtained by heating 
the metal with sulphur. 
Translated into modern chemistry, Italian and Hispano 
Moresque formulas correspond to 
H. Moresque Italian 
a b 
Red ochre 71,98 66,67 49,49 
Silver sulphide .... 1,15 .... 1,03 
Copper sulphide . . . 26,87 33,33 24,74 
Cinnabar .... 24,74 
It will be noticed that the Moresque formula and the 
Italian formula b contain very much the same proportions 
of copper and silver sulphides which are the active factors 
in the formation of metallic deposits. But for a certain 
proportion of red ochre has been substituted in the Italian 
formula, cinnabar or mercury sulphide which at that time 
was frequently introduced, and generally at random, into 
most chemical preparations. 
In formula a there is no silver sulphide, only copper 
sulphide which is sufficient . to give the ruby red metallic 
deposits. This is very likely the famous secret of Giorgio 
Andreoli, who, according to J. Marryat, had obtained it 
from another artist who had preceded him in Gubbio. 
In Moresque faiences, the red which decorated the 
Giorgio ware is never found, because with copper sulphide 
they used silver sulphide which produces yellow tones. 
Brongniart was evidently unfamiliar with these old 
formulas published by Passeri one century before his time, 
as, when he experimented on the production of metallic 
1. G. Passeri — Istoria della pitture in maiolica fatte in Pesaro e ne luogi 
circonvicini dell'abatte Gaimbatista. 1st Ed. Venice, 175S. 2d Ed. 
Bologna, 1775. 3d Ed. Pesaro, 1838; translated into French by H. De- 
lange, Paris, 1853. 
