Sugarloaf

A sugarloaf was the traditional form, a tall gently-tapering cylinder with a conical top[1], in which refined sugar was exported from the Caribbean and eastern Brazil from the 17th to 19th centuries.

"...households bought their white sugar in tall, conical loaves, from which pieces were broken off with special iron sugar-cutters. Shaped something like very large heavy pliers with sharp blades attached to the cutting sides, these cutters had to be strong and tough, because the loaves were large, about 14 inches in diameter at the base, and 3 feet high [15th century]...In those days, sugar was used with great care, and one loaf lasted a long time. The weight would probably have been about 30 lb. Later, the weight of a loaf varied from 5 lb to 35 lb, according to the moulds used by any one refinery. A common size was 14 lb, but the finest sugar from Madeira came in small loaves of only 3 or 4 lb in weight...Up till late Victorian times household sugar remained very little changed and sugar loaves were still common and continued so until well into the twentieth century..."

"English Bread and Yeast Cookery", Elizabeth David [Penguin:Middlesex] 1977 (p. 139)

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Today, such loaves are still common in some parts of Europe, especially in Germany where small loaves are a required ingredient for the holiday season drink Feuerzangenbowle.

References

David, Elizabeth. "English Bread and Yeast Cookery", [Penguin:Middlesex] 1977 (p. 139)