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US2255210A
Expired / Lapsed
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Process for the recovery of tungsten
Assignee: ELECTRO METALLURG CO
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Filing: 1939-04-22
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Granted: 1941-09-09
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Expires: 1959-04-22
Abstract
No abstract record available.
Inventors
- 👤 John J Furey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:56
CPC Classifications
C; C22; C22B; C22B34/00; C22B34/30; C22B34/36
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1944-09-08 | 1945-03-10 | 1945-09-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-09-08 | 1949-03-10 | 1949-09-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-09-08 | 1953-03-10 | 1953-09-09 | $7700.00 | Window Closed / Lapsed |