The pieces that constitute the numismatic proof sets are coins minted in the year engraved on the inside of the six pointed star placed on the reverse of all coins.
The blanks, from which the coins were minted, come from careful selection and have undergone a special cleaning and polishing process.
The dies used in coinage have been specially prepared with polished mirror shine of fields and matting of the reliefs.
The actual minting is performed at a reduced production rate and all final handling is carried out with maximum care.
The coins included in this collection are the corresponding to the minted for 1977, according to the Royal Decrete 30.221/1976, from 12 of November (B.O.E. from 8 of January of 1977).