Glass Marks Identification: Logos on Vintage Glassware
Identify vintage glass by maker's marks, acid-etched signatures, molded logos and labels, and what to do when glassware has no mark at all.
By Ayoub Farid · · 2 min read
Glass is harder to identify than pottery because so much of it is unmarked. But when there's a mark, it's often decisive — and knowing where to look helps.
Where to find marks on glass
- Base: molded logos, acid-etched signatures, engraved names
- Inside the base of bowls and vases
- Rims and feet on some stemware
- Paper labels and stickers (often lost)
Hold the piece at an angle to the light — molded and acid-etched marks can be very faint.
Types of glass marks
- Molded marks: formed in the mold, e.g. letters in a circle or oval
- Acid-etched signatures: frosty, faint script, common on art and crystal glass
- Engraved signatures: scratched by hand or wheel, sometimes with a date
- Enamel or painted marks
- Labels
Common American glass makers
American pressed and colored glass from makers like Fenton, Imperial, Fostoria, Heisey, Anchor Hocking (including Fire-King) and Indiana Glass is widely collected. Some used molded logos (for example Heisey's "H in a diamond"); many pieces carried only paper labels. See Depression glass and carnival glass.
European art glass
Art glass from France, Bohemia, Scandinavia and Italy (Murano) often carries etched or engraved signatures. Famous names are frequently faked, so check that quality matches the signature.
Unmarked glass
Identify by:
- Pattern (compare with collector references)
- Color and how it reacts to UV light
- Pontil marks and mold seams
- Weight and ring: lead crystal rings clearly when gently tapped
- Wear on the base consistent with age
Reproductions
Many popular patterns and makers have been reproduced; some reproductions carry new marks, others mimic old ones. Compare dimensions and details with documented originals.
Scan it
Photograph the glass against a light background and scan it with AntiqueIQ for an identification, era and estimated value range. Then check the base for marks.
Frequently asked questions
How do I identify unmarked glass?
Compare pattern, color, shape and manufacturing marks with collector references, or scan it with an identifier app.
What does an acid-etched signature look like?
A faint, frosted script or logo, often on the base, best seen at an angle.
Is signed glass always valuable?
Not always. Value depends on the maker, design and condition, and signatures can be faked.