Re: What are golf balls made of?

Tough question and I don't think we are going to be able to give you an exact answer. The typical golf-ball construction can be either wound or solid (you described a solid core), each of which offers significant differences in control and feel. Depending on the manufacturer, you might be able to find good information about the exact composition through a patent search but my guess is that the exact composition is considered proprietary so manufacturers are going to keep the exact material composition to themselves. I can help with a bit of general information:

Wound balls have three parts: center, winding and cover (also called three-piece balls). They offer more spin and control but typically less distance.

Solid balls are comprised of two parts, a solid core and cover. These two-piece balls offer more distance but less spin and control.

In general, the core is generally a compound of natural and synthetic rubbers (polymers). Differences in core construction affect spin rate (control), initial velocity (distance) and compression (feel).

Try these links for more information:

Golf ball evolution
US Patent & Trademark Office

Good luck with your search!

Kieran