Hi Llacer SBD,
During the reign of King Carlos III, the octavos and barilla have letter "EMAN" ,"Ms" or the symbol "*" only placed on both side of the dates or coat of arms which indicated that those were minted in Manila. However it changed during the reign of King Carlos IV, Ferdinand VII and Queen Isabela II to F and M or F and MA. Based on the record of the Spanish Mint, there was no specific assayer being mentioned at the beginning of production of these coin that may be attributed to a certain Franciso Delos Reyes. We can only make an assumption based on the analysis of the remaining historical records that it may probably be attributed more to "Filipinas". Aside from that, productions and minting of these coins were mostly conducted by sub contractors outside of the mint, the reason why the coin is very crude of material and finish, the design varies from one coin to another, and quality were very poor. Indicating that several different dies were created for the same date of coins but produced in different manners. However, this claim may still be debatable because of the fact that Spaniards are well known for attributing coins with their assayers which has become a standard in the production of modern day coins. But such standard may not have been followed in the Philippines due to subcontracting. This characteristic has been proven to have continued up to the counterstamping of Philippine coins, which clearly showed that even F70 and YII counterstamps also have several different dies. Showing, that the same practice of outsourcing was utilized by the Spanish government to expedite the manufacture or production of the local coins, possibly either because of corruption or lack of funds.