Kerry, after all the posts, I'm still completely befuddled.
That cueball isn't heavier. So, I'm confused. That green aramith logo cueball has been measured and weighed by many people. It's not heavy. Mine happens to weigh 5.8 oz. The tolerance allowed is 5.5 - 6.0 oz. If you weigh all your object balls, you'll see they are all in that 5.7 - 5.9 range when new.
From previous measurements:
http://groups.google.com/group/rec.sport.billiard/msg/ce31cc21103cc5da?dmode=source
Red Circle 5.9 oz
Blue Circle 5.9 oz
Aramith Logo 5.9 oz
Aramith "pro cup" (red "polka-dot" ball) 5.8 oz
and
http://groups.google.com/group/rec.sport.billiard/msg/ab60251c1beb722a?dmode=source
So, even the Red Circle (a real one, not a fake one) is the same weight as the rest of the balls. Some (Tate) have reported at even slightly heavier by a tenth of a gram. The Red Circle we've found out from Saluc (Aramith) is made from a different resin than the other cueballs. It might be why it's livelier. But, the Aramith Logo (green) is the same weight as the other cueballs.
Fred