The 'Here's to Never Growing Up' hitmaker, who married the Nickelback frontman, 39, at Château de La Napoule in the South of France on 1 July 2013, admitted she is still in shock over his generous gift.
The 29-year-old singer shared a photograph of them, in which she is wearing the dazzling piece of jewellery, on Twitter on Thursday (31.07.14), with the caption: ''I still can't believe my 1 year anniversary gift. 17 carat emerald cut. Wow. I love my hubby (sic)''
The new sparkler is larger than the 14-carat pear-shaped engagement ring the rocker proposed to the blonde beauty with in early 2012, but slightly smaller than her 20-carat emerald wedding ring, which is estimated to have cost approximately $1 million.
The 'Complicated' singer, who was previously married to Sum 41 star Deryck Whilbley, recently admitted she can't wait to start a family with Chad, but insisted they are too busy at the moment.
She said: ''I'm really focused on my career at the moment.
''Down the road, I would love to be a mom, just not right now.''
Chad also previously said: ''We both want [children]. We just need to find a time we're both at home to get around to it.''
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