Hi Christine, yes, I'm fast coming to the same conclusion.
The base wear, which has acquired a shiny appearance ( where the satin finish has been rubbed smooth ) is probably more consistent with the 50s/60s than the 30s.
However they look as if they've been well made - the mottle could also be described as a refined spatter.
Whatever, they're not going back to the charity shop !
Many thanks
Scott