During this period, Spain was in the process of adopting the metric system for weights and measures. It was hoped that such a system would facilitate trade and contribute to overall economic prosperity in Spain. The transition to decimal coinage was intended to reduce complexity of everyday commerce and similarly contribute to Spain's prosperity.

Perhaps the most influential factor in transitioning to a decimal coinage was the fact that many of the coins in use in Spain at this time were French francs which were already a decimal coinage. Spain's new system appears to have been not so much an abrupt departure from eons of Spanish tradition as it was a simple adoption of the current method of exchange into a Spanish form. The people of Spain logically desired, and their economy desperately needed, a coinage system to mimic and combat the dominance of French coinage.

The royal decree of 15 April 1848 introduced Spain's first decimal coinage. Under this system reales de vellón were the sole unit of account. Gold coins would be issued in a 100 reales denomination while silver coins continued largely as before except for modifications to their weight and purity in an attempt to combat their export. The maravedís were abandoned and décimas de real (tenths of a real) introduced as the copper coinage. The designs of all coins were revised to reflect the change in the coinage system.

The first decimal period is defined primarily by the copper coinage denominations based on décima de real (tenths of a real). This is the 1 décima de real. There was only one type of the décima de real (1850-1853). The aquaduct mint mark above the date identifies these coins as being struck at the Segovia mint.

The coin pictured here is an uncirculated example with beautiful coppery iridescent toning, transitioning from dark to light as the coin is tilted and rolled in hand.

The silver and gold coins of this period are characterized by the Looped Braid Head Right type on the obverse. As with the designs of the Kingdom period the engraver adapted the queen's appearance and hairstyle for the coins. The queen often wore a looped braid hairstyle which was depicted in various forms on the decimal coins from this point onward.

This particular coin is well struck with dark toning at edges and subdued luster in those areas. The remaining surfaces are lustrous and devices are sharp with relatively few marks.

Also, beginning in 1850 the assayers’ initials were no longer placed on coins and mint of manufacture would henceforth be indicated on silver and gold coins by stars which appeared at either side of the denomination. Coins minted at Madrid displayed a six pointed star, Seville a seven pointed star, and Barcelona an eight pointed star. Copper coins continued to use the old style mintmarks until the 3rd Decimal period when they also began to employ stars.

The first decimal period is defined primarily by the copper coinage denominations based on décima de real (tenths of a real). This is the 5 décima de real, most commonly referred to as medio real (half real). There were four types of the medio real (1848-1853). They are distinguished by what appears in the area above the denomination on reverse: starburst, plain, small wreath, or large wreath. The first three of these varieties were essentially tests, though a number of plain and small wreath types did enter circulation. The large wreath type was ultimately settled on for production in 1850 and was produced each year until 1853. The example above is of the plain variety and the M mint mark above the date identifies it as being struck at the Madrid mint. Eye appealing uncirculated examples are quite scarce.

The coin pictured here is an attractive uncirculated example with pleasing brown color accented by hints of remaining luster in the protected areas.

The first decimal period is defined primarily by the copper coinage denominations based on décima de real (tenths of a real). This is the 5 décima de real, most commonly referred to as medio real (half real). There were four types of the medio real (1848-1853). They are distinguished by what appears in the area above the denomination on reverse: starburst, plain, small wreath, or large wreath. The first three of these varieties were essentially tests, though a number of plain and small wreath types did enter circulation. The large wreath type was ultimately settled on for production in 1850 and was produced each year until 1853. The example above is of the large wreath variety and the aqueduct mint mark above the date identifies it as being struck at the Segovia mint. Eye appealing uncirculated examples are quite scarce.

The coin pictured here is an attractive uncirculated example with pleasing brown color accented by hints of remaining luster in the protected areas. Lines and hazy areas on the reverse are on the NGC holder, not the coin.

The constant export of Spanish 20 reales during the mid 1800s makes finding an eye appealing example very challenging. This looped braid design by Remigio Vega adorned the silver and gold coins of the 1st Decimal Period. The high points of obverse and reverse dies for this design type are directly opposite each other which, on 20 reales of this type, often results in characteristic weakness in the central hair details on obverse and top of shield, bottom of crown on reverse.

A well struck example for the type. The glowing luster of this coin's devices combine with dusted mirror fields to produce a pleasing semi cameo appearance. A truly rare piece in this condition and certainly one of the finest known examples of this type.