Set in white gold or platinum, blue topaz jewelry has become very fashionable. The contrast between the bright metal and the concentrated blue gemstone creates a very nice look for this December birthstone. Besides its beautiful color, blue topaz jewelry has become popular due to its affordability and its strength. On the Moh's scale of hardness, topaz is an 8. This means that your blue topaz jewelry may be worn frequently and cleaned with gem cleaner to maintain its brilliance. Though it is durable, protect it from scratches, sharp blows and extreme temperature changes.