Blems can mean a lot of things, so you need to ask what the specific imperfection is if you're interested in buying one.  Most commonly it's odd colors or surface pitting.  Neither will have much or any effect on performance.  Instead of normal "pretty" swirling, the ball might be mostly a solid color with a big blotch of the other color all in one place.  Less often the colors come out just plain wrong.  Some are kind of cool, others are just plain ugly.  Blems can also mean things like very short (<1") or very long (>7") pin placements (how far the pin is from the CG).  These don't necessarily make the ball bad or undrillable, but they can limit how you can drill them.  Blems can also have very high (5oz+) top weight.  Again, most of these can be drilled as long as you have a skilled driller, but very high top weights might make the ball illegal no matter what he does.  There are also pro CG balls that might be classified as a blem depending on who you talk to.  These have the CG substantially out of line from the pin mass bias marker.  They essentially make the ball most suited for either a left or right hander depending on which way the CG is off line.

You're probably right, but I think I've seen them listed both ways.  I was just trying to keep it simple and list any imperfections that a ball might have.

Found this on Roto Grip web site:

 

Duke Harding

 

eBay stuff. 

 

Edited by DukeHarding on 10/8/2011 at 4:13 PM

Blems = short for blemishes. Typically associated with defects or blemishes with/on a bowling ball.

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