PTI Crystal Sugar has much larger crystals than regular white sugar. The larger size of the crystals (about the size of pretzel salt) makes the sugar stronger and more resistant to heat. This type of sugar also helps to give baked goods or candy a little texture. Then there is something called decorating sugar, also known as coarse sugar. This type of sugar has crystals that are much larger in size than white granulated sugar, which makes it stronger and more heat resistant. Also known as caster or bar sugar, this sugar has the smallest crystal size of white granulated sugars. It is generally used in making delicate or smooth desserts, such as mousse or puddings. Because the crystals are so fine, they dissolve easily, even in cold drinks.