I quote my previous post.
Because my idea about that kind of bird beads have not been changed.

They are my recent found in Java and I'm sure they are ancient glass beads except one bead.

Almost of them belong to type 3) some are type 2).
And Beads of Type 3) are transparent dark blue, beads of type 2) are opaque black in this time.

Good fakes look like type 3) exist also.

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type 1) - Low quality beads
white motifs are rised on surface.
If you touch the bead ,you feel the motifs.
And after white motifs has gone out,surface is almost flat.
White motifs are not fused well into thier body.
type 1) exist much more than type 2) ans type 3)

type 2) - Midium quality beads
white motifs are rised on surface a litte bit.
If you touch the bead ,you feel the motifs a little bit.
And after white motifs has gone out,you can see the same motif as shallow trace.
White motifs are fused into thier body in shallow.

type 3)- high quality beads
White motifs are not rised on surface.
If you touch the bead ,you don't feel the rise of motifs (surface is almost smooth).
And after white motifs has gone out,you can see the same motif as trace.
It looks like carving and filled with white material as a result.
(I can't judge it's carved or fused well.)
type 3) is difficult to find compared to type 1) and type 2).

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