Hi XXXXXXX - Thank you for using Just Answer
A 1.23 ct diamond means it is almost a carat and one quarter diamond which is a very nice size diamond. The G1 rating means the color and clarity of the diamond on a jewelers scale. Check out this website for all the information about diamonds!
http://www.ajediam.com/Diamond_appraisals_grading_ratings_course.html#anchor_380
The size is nice and the G1 is ok. Thanks for using Just Answer. Renee
Wedding Consultant
I have been a Bridal Consultant, and a Wedding Planner. I own a flower & cake decorating shop