With many of it's former 5th Avenue counterparts [including Rex, Columbia and Zell] Dorset was a big name along 5th Avenue when it came to powder compacts. Alongside their manufacturing of lucite handbags, Dorset produced moderately priced compacts between the 1930s to 1950, by 1951 they had merged with their 5th Avenue rival Rex to become Dorset - Rex and thus discontinued manufacturing under the Dorset brand.
This compact is one currently I have up for auction via eBay - it's unused and probably dates to the late 1940s. I love the attention to detail with the star design etched into the opening to the same design running around the edging of the goldtone case and upon the bottom. While the compact itself remains unbranded, it comes complete with original, unused puff - the name Dorset Fifth Avenue printed across the ribbon band. The compact is topped off with a cross design completed with flowers. For it's age it remains in a great condition - with sturdy hinge and few markings to the patina. It's certainly a lucky find.