From CF Dress Instructions
JEWELLERY BIJOUX
6. The only jewellery that may be worn in
uniform shall be a wrist watch, a service-issued ID
tag, a Medical Alert chain identifier, a maximum of
two rings which are not of a costume jewellery nature
and a tie tack/clasp. Additional rings may only be
worn where they indicate professional standing, such
as an engineer, or are worn with a wedding band as
a single set indicating betrothal or fidelity, e.g., an
engagement or an anniversary ring. Safety
regulations should always prevail, especially in
workshops, warehouses or during operations.