9 or 18 carat gold?

Answer 1

I am about to purchase some gold charms for my Pandora charm bracelet.  My choices come down to same charms in either 9KT or 14KT solid gold.  I understand what the difference is in gold to alloy ratio between the two.  The 9KT charms are less than 1/2 the cost, but I would like them to keep the gold look like 14KT does, virtually for years.  Even though I don't wear the bracelet everyday, the charms that are gold filled have lost their original "14KT look".  How well will the solid 9KT endure?   Thanks to any expert out there who'll take the time to help.
Janie