Serpentine necklace mark CR or RC? STG?

[spyder]

I picked up a necklace today with the mark CR or RC with STG (Sterling) shown below. A beautiful clean necklace. British? American? Any ideas?
It also has 925 on the ear of the clasp on both sides.






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[silverly]

One possibility from the USPTO site:



Word Mark CR
Goods and Services (ABANDONED) IC 014. US 028. G & S: jewelry. FIRST USE: 19910402. FIRST USE IN COMMERCE: 19910900
Mark Drawing Code (5) WORDS, LETTERS, AND/OR NUMBERS IN STYLIZED FORM
Serial Number 74308358
Filing Date August 21, 1992
Current Filing Basis 1A
Original Filing Basis 1A
Owner (APPLICANT) Royal Chain Canada, Inc. CORPORATION CANADA 451 Millway Avenue, Unit 4 Concord, Ontario L4K 3V6 CANADA
Attorney of Record Michael B. Chesal
Type of Mark TRADEMARK
Register PRINCIPAL
Live/Dead Indicator DEAD
Abandonment Date August 11, 1993
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