Was putting books away and found a book entitled "A catalogue of Uniforms" put out by the Museum of the Confederacy (Dated 2000).
There are two pictures in the book showing six-pointed stars on the collar.
Page 18 - a picture of the frock coat of MG Bryan Grimes, with a larger six-pointed star visible.
Page 25 - a carte-de-visite of MG Benjamin R Gardner. It is kind of an odd angle, but looks like there is a six-pointed star on his collar.

JIM T