Wedding and engagement ring purity

[LydiaNiz]

I have no first hand experience of this, but have been asked often lately.
Is it really not advisable to have different carats of gold worn next to each other. A customer wants to wear a 9ct red gold ring next to a 22ct one. Thoughts please!
ETA: I've never worked with 22ct, is there a great difference in working with it compared to 18?

[joella]

i have been told this too Lydia, as the harder metal would wear away at the softer - but I don't know if it's correct.

[metalsmith]

You might choose alloys to inform your customer / work with based on the table on this site (https://24carat.co.uk/hardnessofgoldalloysframe.html)

[LydiaNiz]

thanks, the 22ct was a family piece, I might suggest it worn alone.