As the most highly coveted product of the New World the presence of 27 gold bars and 12 gold bits amongst the “Tortugas” assemblages is unsurprising on a ship of the 1622 Tierra Firme fleet. The material may be interpreted as payment received for outward-bound private consignments shipped to the Americas from Seville.
The gold bars were clustered in two areas of the wreck: off the north/northwest stern zone and east/west between midship and the stern. Specific types were also nucleated. Examples stamped ‘EN RADA’ were centrally clustered, deposited east to west, while the thinner ‘SARGOSA’ bars were concentrated off the stern.
The gold bars vary substantially in states of completeness. The lengths of the differently preserved bits and bars vary from 1.2-25.4cm and weights from 2.50gms to 1.224kg and purity stamps from 20 to 22 karats. ‘SARGOSA PECARTA’ stamps occur on eight bars, ‘EN RADA’ on seven bars and ‘SEBATN ESPANOL’ on just one example. Quinto tax stamps and karat purity indicators are presented on all bars (Figs. 22-28).
All the various impressed marks stamped on the bottom surface of the bars, confirming the payment of the 20% royal quinto tax, plus numerals and characters signifying the purity of the gold, were struck into the molten bars after casting. Purity was marked in Roman numerals (such as XXI for 21 karat purity) set in rectangular frames; above appeared solid dots enclosed by smaller rectangular frame denoting fractional values (one dot for one-quarter karat, two dots for a half, etc). The word ‘EN RADA’ appears with several co-joined letters (P and L, A and E, and R and A and N). Other stamps read ‘SARGOSA PECARTA’ and ‘SEBATN ESPANOL’.
These stamps represent abbreviated names of the Antioquía foundries of the Colombia mines where this colonial gold was extracted and cast. The ‘SARGOSA PECARTA’ gold bars derived from Zaragoza, which started operations in 1582, while ‘SEBATN ESPANOL’ signifies extraction at the seemingly small San Sebastian mines of Timaná. The ‘EN RADA’ gold is an abbreviation of ‘Peñarenda’, a wealthy family that owned gold mine concessions in various parts of the New World, including seemingly Colombia and Mexico. Different mines seem to have processed the bars in minor contrasting styles. The ‘SARGOSA PECARTA’ stamped bars exhibit tapered, almost pointed ends, and an assayer’s bite cut from the end of the bar. On the ‘EN RADA’ bars, which incorporate blunt, almost squared off ends, the assayer’s bite is found at the end’s center.
An important contribution of the “Tortugas” assemblage is evidence of production and function. The collection mainly comprises half and quarter examples, which have been cut for convenient use. These breakage patterns display little functional rationale. An estimate of the required weight and size was simply sliced off as demanded. Obsessive repeat stamping on intact bars demonstrates that such fragmentation was a functional expectation. Efforts were consistently made to preserve a segment of the tax stamp on every piece to confirm that the king’s tax had been honored. The presence of even slight royal tax marks on smaller bar fragments would have lent reassurance during exchange and commerce regarding the validity and respectability of a merchant.