Thanks!
I thought a lot of it was shipped back to Britain but my friend says it was shipped back to Britain ready to sell as "pure white sugar".
Sugar cane was turned into raw sugar on the plantations in the West Indies, but refined close to the market in the consuming countries.
Sugar cane, after being cut, was pressed in a sugar mill on or near the plantation. The juice was then heated, clarified, and boiled to make “massacuite”. The massacuite was then poured into conical molds. The molasses would run out by gravity over days or weeks through the bottom (pointy end) of the mold, leaving a cone of raw sugar behind. At this point, the sugar cones and molasses would be exported from the West Indies (except that portion used for local consumption or to locally make rum). (Nowadays, the “massacuite” is generally separated into sugar and molasses centrifugally at industrial scale.)
Refining the sugar was usually done at the destination. The raw sugar would be melted down, impurities removed, and then re-crystallized as refined sugar, 100% sucrose.
In sailing ship days, it made sense to refine the sugar after shipment, as it could be damaged during transport, but such damage would be eliminated by refining. The sugar islands of the Caribbean, also did not have a large source of fuel to support both the initial boiling of the sugar and the later refining, so it made sense to do this where there was more coal.
So, almost all the sugar produced in the West Indies in the heyday of sugar there was made into raw sugar in the West Indies but refined nearer to the markets. This is less true today as new processes allow a single process to make 99.5% sucrose sugar (called “plantation whites”) which competes with refined sugar, nevertheless, most sugar is still refined near consumption, not near production.
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