It's not easy. If you have a lot of, say, 8mm bicones of both glass and crystal, you could weigh them (the glass separately from the crystal). The crystal should weigh more than the glass. However, if you want to tell Swarovski crystal from non-Swarovski crystal, there are a few characteristics to check. First of all, all Swarovski beads will be cut the same, whereas non-Swarovski beads will vary in cut quality, style, and facet placement. Second, Swarovski colors saturation will be consistent throughout each color and each bead. Non-Swarovski colors may fade or separate within the bead. Third, drilled holes in Swarovski beads will be centered, consistent, and not overly large in each and every bead. In non-Swarovski beads, drilled holes may be on an angle/not true vertical, may be 1mm or more in diameter, may not be centered in every bead, and you might see more than one hole drilled in, say, an 8mm cube. Finally, in the case of an aurora borealis finish, the Swarovski beads will exhibit a subtle iridescence, but the non-Swarovski beads will exhibit an obvious, coated iridescent effect.
Glass beads are heavier than plastic
There are many ways to tell glass from semi precious stone beads. EHow has published an article on how to tell glass from semi precious stone beads, which describes how to inspect the sound, texture, bead, and cut of the specimen.
Most of the time it will. Good crystal always will. You can tell crystal from glass by lightly tapping the side of the glass, vase, or item. When you do this you will get a ringing sound from crystal and a "thump" sound from glass.
Glass
Crystal and glass are the same thing. Crystal is glass that contains lead. When lightly tapped it has a sharp ring compared to plain glass.
Cindy Jenkins has written: 'Beads of glass' -- subject(s): Glass artists, Glass beads, Glass blowing and working, Technique 'Making glass beads' -- subject(s): Glass beads, Glass blowing and working
Its see through and sparkles??????
Faux crystal is normally pressed glass rather than hand cut. You can normally tell by finding the mold seams in the glass.
Lampwork glass beads are often used to make jewelry. Some examples of this jewelry can be found online at Lampwork-Beads-Glass, Zacoo, and Lima Beads.
If you tap your glass bead on glass it will make a "sharp" sound. If you tap your bead on glass and it makes a "dull" sound, it is most likely not made of glass.
The most sustainable beads are pearl beads. They are much stronger and last much longer than glass beads. This is one of the reasons they cost more than glass beads.
Louise Mehaffey has written: 'Glass beads' -- subject(s): Glass beads, Glass craft, Glass blowing and working