Three types of blown/hollow Bohemian beads, not faceted, but found together
mixed with regular “Russian blue” in the Port Harcourt area.
Size: from 7mm round to 13 x 7mm oval
Beads in center are shorter but somewhat similar in construction
to some beads on the Levin sample card "Traded for slaves".
They are also seen in different colors on page 282/283 in “Beads from Gablonz” from Waltraud Neuwirth.