As noted by Bob L...it looks as if you have a 586-3 from 1989. I'm attaching copy of a portion of Mr. Jinks letter about Glass Bead (Matte) Finished 586's from 1989 run. Also, you may find the following link from S&W Forum useful.
Gun show find 586-3 6" round butt blue matte finish
Hope this info is helpful.
Ray