Sometimes it helps to be devious - er, creative...

Dating mail order patterns can be tricky.  If you've got the mailing envelope, sometimes you get lucky with a date on the postmark, or a postage meter that can be narrowed down to a particular timeframe.  Sometimes all you've got to go on is hairstyle in the pattern illustration.  And sometimes, you can find a way to get sneaky...

The one i'm listing today has no date, a postage rate that doesn't seem to narrow things down much, and a hopelessly blurred postage meter number (yep, you can try to look up the meter number - there are folks who collect and track metered postage as a hobby, and they're online too).  My knee-jerk reaction to the illustration was that it was late 1970s - but could i pin it down at all?

The dress style is the sort that might crop up in a wide range of years, so no help there.

But it turns out, this pattern, from Grit, also advertised a bunch of craft booklets on the back of the envelope.  There, i hoped, was my ticket.

A few quick searches later, i found copyright dates of 1977 and 1978 for such titles as "Thrifty Crafty Flowers" and "Envelope Patchwork Quilts" - bingo!  Enough to suggest that my initial guess was probably pretty close...