I found this on PETA:
Are animal ingredients included in white sugar?
Bone char, which is used to process sugar, is made from the bones of cattle from Afghanistan, Argentina, India, and Pakistan. The bones are sold to traders in Scotland, Egypt, and Brazil who then sell them back to the U.S. sugar industry. The European Union and the USDA heavily regulate the use of bone char. Only countries that are deemed BSE-free can sell the bones of their cattle for this process. Bone char—often referred to as natural carbon—is widely used by the sugar industry as a decolorizing filter, which allows the sugar cane to achieve its desirable white color. Other types of filters involve granular carbon or an ion-exchange system rather than bone char.
Bone char is also used in other types of sugar. Brown sugar is created by adding molasses to refined sugar, so companies that use bone char in the production of their regular sugar also use it in the production of their brown sugar. Confectioner’s sugar—refined sugar mixed with cornstarch—made by these companies also involves the use of bone char. Fructose may, but does not typically, involve a bone-char filter. Supermarket brands of sugar (e.g., Giant, Townhouse, etc.) obtain their sugar from several different refineries, making it impossible to know whether it has been filtered with bone char.
If you want to avoid all refined sugars, we recommend alternatives such as Sucanat and turbinado sugar, which are not filtered with bone char. Additionally, beet sugar—
—though normally refined—never involves the use of bone char and Edward & Sons Trading Company has developed a vegan confectioner’s sugar which should be available in health food stores soon.
It would be virtually impossible for PETA to maintain information on the refining process used for the sugar in every product. We encourage you to contact companies directly to ask about the source of their sugar.
The following companies do not use bone-char filters.
2600 S. Euclid Ave.
Bay City, MI 48706
Florida Crystals Corporation
P.O. Box 471
West Palm Beach, FL 33480
Western Sugar is a subsidiary of Tate & Lyle (formerly Domino sugar) which does use bone-char filters. However, Western Sugar makes only beet sugar, which does not use bone-char filters.
7555 E. Hampton Ave., Ste. 600
Denver, CO 80210
The following companies do use bone-char filters. Contact them and encourage them to adopt the use of humane alternatives to bone-char filters.
C&H Sugar Company
2300 Contra Costa Blvd., Ste. 600
Pleasant Hill, CA 94523
P.O. Box 335
Savannah, GA 31402
Tate & Lyle North American Sugars Inc. (formerly Domino Sugar)
1100 Key Hwy. W.
Baltimore, MD 21230
P.O. Box 9
Sugarland, TX 77487
Refined Sugars Inc.
1 Federal St.
Yonkers, NY 10702