Glass · a closer look
Federal Glass Co mark: HEAT PROOF F USA
Mark details
- Maker
- Federal Glass Co →
- Period
- Undated
- Wording
- HEAT PROOF F USA
- Appearance
- F in a shield with curved HEAT PROOF above and USA below
- Type
- embossed
- Material
- glass
- Place
- Columbus, Ohio, United States
Dating cue
Added HEAT PROOF and USA identify this tableware format; a mould number does not date the mug.