This is the perfect size for a gemstone stud earring.  Not too big where it's gaudy nor too small where you cannot see much color at all.  These are what I refer to as the Goldilocks size; just right.
 
And just right these are.  These rubies (oh yes, they're real!) have incredible depth of color and are an absolute treat for anyone to wear.  Classic brilliant round cut, these will be a forever favorite. 
 
- genuine ruby
- 5mm diameter
- 925 sterling silver
- rhodium plated