Assayers’ initials
by Alberto Pradeau
In order to understand the meaning of the assayer’s initials on the coins of New Spain, it becomes necessary to review the Spanish minting laws.
Ferdinand and Isabella, by ordinance of 13 June 1497[text needed], decreed:
". . . that the assayers shall mark the coins with a sign or mark which must be recorded with the notary of the mint, said mark or sign to be kept in the notary's book so that . . . if any gold or silver coin is found of low fineness, the sign or mark borne by such coin, will serve to identify the assayers responsible for the error, who shall then be punished accordingly."
This document speaks of assayers and justly so, as in all mints there were two chief assayers. HerreraHerrera, El Duro, p. 104 quotes the following:
"As the royal ordinance of 16 July 1730, did not specify, as it had been the custom, that the assayers' initials should be placed on the coinage, the Superintendent of the Madrid mint, on 13 September 1730, consulted this point with the Secretary of State, and on 15 November of the same year, obtained the following answer:
'It is his majesty's wish that the sign to be borne by all coins minted in his realms, shall be as provided by former ordinances, the initials of the assayers of each mint.' "
The above is found corroborated in the ordinance of 1 August 1750[text needed] issued by Ferdinand VI, and reprinted in MexicoImprenta del Br. D. Joseph Antonio de Hogal—1771, chap. XIX, dealing with the formalities of coining, assaying, counting and delivering the batches. In part it says:
". . . in the presence of the Accountant, Treasurer, Assayers, Fiel de la moneda (inspector of weights and measures), Juez de la Valanza (overseer in the weighing of coins), the Keeper of the dies, and the Notary, the Superintendent of the mint shall draw from every batch three coins of each denomination, two of which are to be sent to the Spanish Cortes and the third one to be cut in half. The half bearing the year of coinage and the initials of the two assayers must be kept by the superintendent, while the other half is to be divided into two pieces, one for each of the two chief assayers (ensayadores propietarios), who independent of each other, must proceed to assay the portion given to him and certify as to its fineness."
Chapter XXV of the same ordinance very precisely specifies that the Mexico mint was to have four assayers, two of whom were to be chief assayers (ensayadores propietarios) and the other two were to be assistant or substitute assayers (ensayadores supernumerarios).
Thus, the initials as found on the coinage of New Spain represent not the mint master's name but the first letter of either the given name or surname of each of the two chief assayers assigned to the Mexico City mint. However, not until 1731 did the two initials appear on the coinage.