Antique Sterling Silver Royal UK Order of the Garter Medal

This sterling silver, slightly domed medal features an enameled centerpiece, the Royal Coat of Arms of the United Kingdom, encircled by the French motto of the Order of the Garter ‘HONI SOIT QUI MAL Y PENSE’ (Shame on him who thinks evil of it). Above the coat of arms is a crown, signifying a connection to British royalty or a related institution.  
 
According to Wikipedia, the Most Noble Order of the Garter is an order of chivalry founded by Edward III of England in 1348. The most senior order of knighthood in the British honours system, it is outranked in precedence only by the decorations of the Victoria Cross and the George Cross. Appointments are at the Sovereign's sole discretion, typically made in recognition of national contribution, service to the Crown, or for distinguished personal service to the Monarch.[2] Membership of the order is limited to the sovereign, the Prince of Wales, and no more than 24 living members, or Companions. The order also includes Supernumerary Knights and Ladies (e.g., members of the British royal family and foreign monarchs).
 
This was found in our late grandmother’s family mementos, suggesting someone in her family received this in the late 1800s or early 1900s. 
 
On the back of this piece is stamped STERLING. The piece could use a polishing, but is otherwise in very good condition for its age. We could not however figure out how it would be attached to anything other than maybe a thin tie slipped through the side slot on the back. Please let us know if you know more!
 
H 2 1/4” x W 1 1/4”
Approx. 0.5 oz (14g)