ASSOCIATE OF ST. PETER (religious fraternity?) - an Associate's membership silver medal (hallmarked for 1959)

Postage is extra.

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For sale is a vintage religious silver medal with the obverse text ASSOCIATE OF S. PETERS - WATCH AND PRAY. The association's crest is displayed on the medal.

The reverse side is plain with a hallmark for Birmingham 1959 (K) and the maker's mark W.J.D. (William James Dingley).

Unable to track down this association and if anyone can confirm which one it is, I'd be grateful to hear from you.

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DESCRIPTION:
Size: about 7/8" x 1 7/16" including the bale (22mm x 36mm).
Material(s): hallmarked sterling silver.
Finish: n/a.
Fitting: bale to take a suspension ring.
Imprint: none. Hallmark details; Birmingham 1959 (K) and maker's mark W.J.D. for William James Dingley of Warstone Lane, Birmingham.
Approximate age: 1959/1960.

CONDITION:
Very good condition. No damage. Some minor wear on high-relief details, commensurate with age and use.
Please see photograph(s), these form part of the description.

POSTAGE:
* Postage costs are extra, additional to the Asking Price.
* I always get a proof-of-posting certificate.
* I combine postage costs for multiple items when these are paid for and posted the same time.

RETURNS:
* Return accepted if the item(s) is returned in same condition it left me, then the full Agreed Asking Price will be refunded. Postage costs are not refundable.
* Buyer pays the return postage costs - unless agreed otherwise.

B.40