Two of our favorite beaches seem to churn up these very rounded, almost marble-like spheres of sea glass.  They are beautiful, smooth, rare and they have become one of our favorite types of sea glass to design with.  Each "bauble" usually measures at least 1/2" across.

Rare golden yellow sea glass from England on 3/4" sterling pins, on sterling leverbacks. w/copper beads.

Aqua blue sea glass spheres from the rugged Pacific on 1.5" sterling pins, on sterling leverbacks.