Every time I see the HA mark, I dither over "is it Anchor-Hocking or Hazel-Atlas?", then I reach for a book. My books aren't the newest, so now I'm going to hedge my bets again -- maybe 'Historic' has some newer evidence than presented in my old books. But... Arthur Peterson's 1968 booklet "400 TRADEMARKS ON GLASS" on page 49 in final chapter "Some Trademarks Introduced After 1914" lists "H straddling an A, in a circle. Hazel Atlas Glass Corp., Wheeling W.Va --1923." [sic - no idea the significance of '--1923']
Hazel Marie Weatherman, long-time 'queen' of Depression Glass, says in the 1974 edition of one of her books about molded/pressed tableware for which the company is best known by glass collectors: "Hazel-Atlas did not plant color into its lines until 1929... A deep blue Hazel-Atlas called 'Ritz blue' was developed for 1936." Weatherman also writes, though, the company resulted "...from 1902 merger two Washington PA 'container firms' of Hazel Glass Co. & Atlas Glass & Metal Company." The Weatherman books all conspicuously display the H-over-A trademark, but since her research is of pressed tableware, her comments may not apply to original H-A factories making "containers" (i.e. bottles?!) where an earlier deep cobalt blue shade might have been in production. Anyway, "Fairly common...a few dollars decorative value."