3 Dot Variety. NGC VF Sea Salvaged. 
Another Crown Jewel of the Knapton Collection the most advanced esoteric shipwreck coin collection currently assembled. 
This coin is one of the FIRST EVER struck in the New World and is 1 of 4 Known of this Variety.
In her article "Varieties of Rincón Three Reales of Mexico Charles- Joanna" Cori Sedwick conducted a die study and concluded that the 3 dot variety with water under pillars were the first coins struck in Mexico when the mint opened in 1536. By royal decree, 3 Reales were to be paid to each mint official for every mark of silver they coined. Nesmith states that the pay was actually 2 Reales, Sedwick theorizes this on top of the unpopular design of the calm water below the pillars were the reasons why this design and denomination were discontinued A modified water below pillars design would return with the late series design beginning in 1542.