Silicon carbide gemstones
CA 2230262 F · Owner: Verbiest, Dirk · Inventors: Hunter, Charles Eric; Verbiest, Dirk
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Synthetic gemstones having extraordinary brilliance and hardness are formed from large single crystals of relatively low impurity translucent silicon , carbide of a single polytype that are grown in a furnace sublimation system. The crystals are cut into rough gemstones that are thereafter fashioned into finished gemstones. A wide range of colors and shades is available by selective doping of the crystal during growth. A colorless gemstone is produced by growing the crystal undoped in a system substantially free of unwanted impurity atoms.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed August 27, 1996 and granted February 13, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 27, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 27, 2018.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.