My rings are 6 3/4, you can see them in my avatar. My center stone is a 1.5 RB. My ring finger on my left hand is a size 7...but I wouldn''t call it FAT...I attribute it to the fact that I''m 5''10" LOL!
Also, if you go to SMTR there is a super long thread called the e-ring eye candy folder, I believe. Most of the posts there contain hand pics and include finger sizes as well.
I have fat finger syndrome (my pinky is especially chubby!). My ring finger is about a 7 1/4 in summertime and closer to a 7 the rest of the time. I like my rings on the looser side, so my engagement ring is size 7 3/8. The diameter of my diamond is 5.55 mm (0.70 carats).
! I'm just a tad over 5' so if I gain 5lbs I look like I gained 20 lol.....
. At least your fingers are longer, so your hands won't look proportionally odd with the rest of your body. I think you are right; sometimes it isn't finger fat. With the exception of my pinky I think I just have thick finger skin
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What shapes are you thinking about? To get a feel for proportions I suggest thinking about the ideal amount of finger coverage you desire. My diamond only covers about 1/4 the width of my finger. If you go with an oblong stone (rectangular emerald cut, marquis, oval, etc) and set it east-west, you can get more finger coverage horizontally rather than vertically if that matters to you.