US2931351A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polishing hard crystalline carbon
Assignee: De Beers Consolidated Mines Ltd
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Filing: 1958-04-22
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Granted: 1960-04-05
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Expires: 1978-04-22
Abstract
No abstract record available.
Inventors
- 👤 Jan F H Custers
- 👤 Henry B Dyer
- 👤 Peter T Wedepohl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:11
CPC Classifications
B; B24; B24B; B24B9/00; B24B9/02; B24B9/06; B24B9/16; B24B9/166; B24B29/00; B24B29/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
69 words
A METHOD OF POLISHING A DIAMOND COMPRISING THE STEPS OF SUBJECTING THE DIAMOND TO THE ACTION OF A FLAME HAVING AN EXCESS OF ACETYLENE TO HEAT THE DIAMOND TO A PREDETERMINED TEMPERATURE, AND THEREAFTER SUBJECTING THE DIAMOND TO THE ACTION OF A FLAME HAVING AN EXCESS OF OXYGEN FOR A TIME PERIOD SUFFICENT TO REDUCE ASPERITIES IN THE DIAMOND AND GLAZE THE DIAMOND SURFACE TO A SUBSTANTIALLY UNIFORM POLISH.
Claim 2
Independent Claim
69 words
A METHOD OF POLISHING A DIAMOND COMPRISING THE STEPS OF SUBJECTING THE DIAMOND TO THE ACTION OF A FLAME HAVING AN EXCESS OF ACETYLENE TO HEAT THE DIAMOND TO A PREDETERMINED TEMPERATURE, AND THEREAFTER SUBJECTING THE DIAMOND TO THE ACTION OF A FLAME HAVING AN EXCESS OF OXYGEN FOR A TIME PERIOD SUFFICENT TO REDUCE ASPERITIES IN THE DIAMOND AND GLAZE THE DIAMOND SURFACE TO A SUBSTANTIALLY UNIFORM POLISH.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-04-05 | 1963-10-05 | 1964-04-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-04-05 | 1967-10-05 | 1968-04-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-04-05 | 1971-10-05 | 1972-04-05 | $7700.00 | Window Closed / Lapsed |