Date Your Records Pressed by Monarch

Monarch Records
4852 W. Jefferson Blvd.
Los Angeles, CA

Δ Delta Numbers

Monarch Records in Los Angeles, California, started pressing vinyl 45 rpm records in July of 1954. To keep track of the orders, they put a small triangle, the Greek letter delta (Δ), next to a unique number on each side of every record they pressed. Amazingly, they stayed with their numbering system consistently for decades. They did a lot of business with small, independent labels but they also did large quantities for the major labels when they had a hot 45 and needed extra copies.

Below is a chart that can be used to date the records they produced. In using this chart, the numbers below represent approximately the mid-point of the production for each month.

Some labels which have had the Δ number include; ABC, Abner, Ace, Aladdin, Apollo, Argo, Arvee, Atco, Atlantic, Backbeat, Bigtop, Cadence, Cameo, Carlton, Challenge, Chancellor, Checker, Chess, Class, Dolton, Dot, Duke, Ember, End, Era, Gee, Gone, Josie, Jubilee, Laurie, Liberty, Parkway, Roulette, Sue, Scepter, Sun, Swan and Vee Jay.