Cox's jewellery designer friend Jenny Meyer Maguire (she's Tobey Maguire's wife) posted a picture of the sparkly rock on her Instagram page with the caption 'I guess he liked it so he put a Jennifer Meyer ring on it!! Xo'.
Cox' fiance Johnny McDaid proposed to Courteney last month whilst the two were on a romantic getaway in Turks and Caicos to celebrate her 50th birthday.
The couple were said to be 'totally in love' by an onlooker who spotted them on a secluded part of the beach as they sharing a cocktail and relaxed side by side.
After returning from their holiday, Courteney couldn't contain her excitement and tweeted 'I'm engaged to him!' while the Snow Patrol star wrote 'I'm engaged to her!' on his own account.
Courteney and Johnny have been dating since 2013, after being introduced by mutual friend Ed Sheeran. Courteney had previously been married to actor David Arquette, but the two separated in 2012 and divorced the following year after 14 years of marriage. Courteney also had a daughter with her former husband, Coco, who is now ten years old.
Courteney isn't the only one who loves Jennifer Meyer's jewellery. In recent years everyone from co-Friends star Jennifer Aniston to Mila Kunis and Emma Stone have been seen sporting necklaces, bangles and rings by the designer.
Like a bit of bling? See more stunning celebrity engagement rings below:
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