a band keratopathy (calcium in the cornea) and cornea arcus (cholesterol in the cornea) are usually easily distinguished by an ophthalmologist. See an ophthalmologist to determine which it is. Find an Eye MD near you at www.aao.org
JCH MD
I too have recently noticed this condition in my drak brown eyes...if you go to this link I found you'll see pictures and suggestions as to care and/or test needed to be certain of the cause..
http://sphynxcatvp.nocturna.org/faq/most-ringaroundtheiris.html
according to that site it can be Calcific Band Keratopathy , caused by several things , thay recommend a complete metabolic/chem20 blood test and a cholesterol panel to determine if it's a calcium issue, cholesterol or something else...
Speedy03 is absolutely correct.
JCH MD
It is called arcus senilis. It may be cosmetically undesirable but does not affect vision.
If the light blue iris ring you are seeing is at or near the margin between the iris (colored part of your eye) and the sclera (white part) and forms a large ring around that margin it is likely to be a deposit of cholesterol. It does not damaging to the eye and does not interfere with vision. This is very common in older individuals but if you are a young adult it may suggest high cholesterol. If the ring you are seeing is anywhere else on the iris other than following the outside margin, it should be checked.
Nothing I don;t think. My grandpa has that too. Always has.