Well, let's start with some basic questions.
1) Where did you find these rocks? (Location can help narrow the possibilities)
2) What makes you believe the smaller one is topaz? (I'm NOT saying it isn't topaz, I'm just trying to ascertain what tests you've done or what characteristics you can see firsthand that would lead you in the direction of topaz.)
I'm not an expert on anything, but I like to guess based on what little knowledge and experience I do have. So I'm guessing the larger rock is jasper - a common Pacific NW rock - lots of the stuff here in Northern California, for example. And I'm guessing the smaller one is a beach agate. Did you happen to find these rocks in a coastal stream or at the coast near the mouth of a stream?