Ruby is estate 21 in St. Croix’s Queen’s Quarter. Based on appearances on historic maps, the windmill was likely built in the 1760s and decommissioned before 1856. Field reconnaissance failed to locate ruins identifiable as a windmill.
The 1750 map indicates sugar cultivation but no animal mill in estate 21. An animal mill appears on both Beck printings from the mid-1750s. A windmill first appears on the annotated map from c.1770.
The 1799 Oxholm map shows a windmill at Ruby. The 1856 Parsons map depicts a tower with no sails at elevation 230 feet at Ruby. None of the 20th-century topographic maps show a structure identifiable as a windmill at Ruby.
The 1750 map attributes ownership of estate 21 to Josias Webbe. The maps from the 1760s and 1770s attribute ownership Peter Heyliger. By 1790 ownership transitioned to Heyliger heirs.
McGuire geographic dictionary of the Virgin Islands (p.161) notes the historic connection of Ruby and Diamond, immediately to the south.