With respect to these particular coins, rarity comes not only from their very small initial mintages but also from the fact that very few of these coins have even survived in UNCIRCULATED condition. It has been suggested that the reason why these particular coins managed to escape circulation is that they were originally intended as MINT PROOFS or PRESENTATION PIECES given to some high official of the Spanish government or perhaps to an official of the mint on some special occasion (the opening of the mint?).

To ensure perfect detail and quality of execution of these special coins, the dies were meticulously cleaned; specially prepared planchets (alloyed metal plates to be used for making coins) were cleaned and checked for surface irregularities, imperfections and the slightest degree of warpage; the coining machinery was slowed down and the planchets hand-fed (normally, this procedure was automated) to ensure the deliberate and accurate striking of the coins. Very often, in order to ensure a perfect strike, more than ordinary pressure was applied on the dies and the coin was struck not once but twice. It is no wonder then that after all of these preparations, the resulting coin was both visually and technically superb. In more recent times, the minting of proof coins would also require the additional preparatory step of polishing the planchets to be used to a mirror-like finish to achieve a gem-like effect. Mintage is EXTREMELY LIMITED. (Both sets from Philippine collections)