I was really pleased to find these on eBay. Painted by Marjorie Batt in the late 1920's or early 30's, this simple pattern, with the yellow and grey, is very effective. It's also not a pattern I'd seen before and it suits an egg cup very well, as it looks pretty much like the cartoon broken edges of an egg shell, with of course yolk yellow inside. Originally there would have been one more companion, together with a matching tray.
Unfortunately though, it's not just the egg sells that have that been cracked in the past and each pot has quite bad damage. So a bit of a disappointment when they arrived in the post, but the seller at least agreed to refund half the cost, and I am now spurred on to find the missing (and in my dreams perfect) fourth pot.