The London-based Hayman family itself originally supplied a similar style of gin to the Royal Navy under the 'Senior Service Gin' mark, and the 57% ABV is the alcohol content required to set gunpowder alight if the gin were spilt on it.
The Royal Dock name represents the yard in Deptford, on the river Thames in South London from which naval ships departed.
Described by distributor Love Drinks as a gin with a "robust and bright profile with an enhanced citrus and floral aromatic nose", the new drink (pictured, and still distilled by the Hayman family) is available from Speciality Drinks in the UK from £19.75 (US $31.43) for 700ml.