would agree with Sue that the appearance of the decoration gives a nod toward art deco - angular, geometric and stylized. This doesn't mean these particular pieces originated in the late 20s or 30s, which is what folk think of as the art deco period - 'art deco' is simply a decorative style, and appears on many domestic items throughout the C20, though glass and ceramics are what mostly come to mind.
I'd suggest the decoration here is wheel engraved, rather than the wet acid process of being etched. Wheel engraving has some similarity to how images are produced on cut glass, except that with wheel engraving the cutting is generally very shallow, and - as with the leaves seen on the design here - parts of a design are left matte and not polished. This creates areas of contrast (dull and bright) which allows the engraver a greater artistic licence and is more suitable for pieces like these which are thin.
Despite the waffle, regret I've no idea as to the origin or date of these pieces but, again, I'm with Sue in suggesting Eastern Europe - possibly Czechoslovakian/Bohemian.

Do you know if these were, as with the green bottle and tumblers, possessions that belonged to your Mother?