Feild's description of QV's Bar Brooch (1987 pg 65, 1992 pg 77) states "Later she had them reset as a double bar brooch, which she left to the Crown in her will, its description tucked away in a long list of jewelled Orders".
Here is a link posted by Nellie depicting the "Garter Jewels" presented to QM. These are what I was thinking of when I used that term.