Modern balls start with a urethane base and additives are put in it to get different effects. Pretty much every ball has some sort of reactive additive, there are very few real urethanes left.
There are five basic types of coverstock used today: plastic, solid reactive, pearl reactive, solid particle, and pearl particle. Plastic has no additives (not even a urethane base), very low friction, mostly for spares.
The "normal" reactive ball with the fewest additives is the solid reactive. Medium length, will skid some in oil and react to dry boards in the backend.
To the solid reactive you can add finely ground mica to make pearl reactives. The mica stiffens the coverstock so that there's less flexing where the ball contacts the lane. Less flexing means less friction, which is why pearls tend to go longer than solids. They won't react quite as much to drier boards because of that reduced friction. That's one reason you see people using pearl balls when the heads and midlane are broken down, when the oil has been dried out or removed by earlier play.
You could add particles to a solid reactive base to make a solid particle coverstock. The particles can be all sorts of things from rubber to ceramic to glass beads to (I think) diamond (someone once said that Legends used industrial diamond). The canonical analogy is snow tires vs. racing slicks. The particles protrude from the surface (microscopically) to give added traction in oil just like the treads on snow tires punch through the snow to the pavement below. Because particle balls can find more friction earlier, they don't react quite as suddenly to the dry boards in the backend.
You control how much particle is added to the reactive base. Higher loads means more studs meaning more friction. Lower loads mean less friction (above the reactive base's friction). High load particle balls might require a LOT of oil to reduce the friction they see, otherwise they'll hook too soon and use up all their energy. Low load particles are more like all-season tires. Some studs to prevent slipping, but smooth enough to not need a large amount of oil.
You could also add both the particle and the pearl to get a particle pearl. Reaction-wise, they are usually very similar to solid reactives. The effects of the particles and pearlization sort of cancel one another out: the pearlization helps reduce the friction that the particles generate, the particles help find friction that the pearlization reduces.
Sounds stupid, right? It is.
Just kidding. Like every other coverstock type, particle pearls have their place. They can be smoother than solid reactives and not skid as much as pearls when there's carrydown (some of the oil in the front part of the lane has moved to the back, reducing the available friction in the backends).
Polish on a bowling ball makes changes in friction much more dramatic. When there's oil, even a little bit, it helps the ball skid. When there's dry, it helps the ball react.
Sanding a ball does the opposite, it blends the changes in friction by increasing friction when there's oil and reducing friction when there's dry (it doesn't really reduce friction there, but the ball doesn't usually have as much energy by the time it gets there so there's less reaction).
All these types of balls hook. None necessarily hooks more than another, it's very dependent on the amount of oil on the lane and the condition of the ball surface. A very dull pearl will find friction in the heaviest of oils, and if you can polish up a high load particle ball enough, it'll skid in even the lightest of oils. But they all have their "native" lane conditions and their natural characteristics can be enhanced by the appropriate surface.
That's why you see most pearls coming polished from the factory (sometimes a high gloss, sometimes a compound finish like Brunswick's Rough Buff). The polish adds to the pearlization to reduce friction in oil and increase reaction on the dry.
Likewise for particle balls. Not a lot of factory-polished solid particles because you usually want them to help you find friction and the polish does the opposite. You want duller surfaces because that helps create early friction, just like the particles want to do.
Solid reactives and particle pearls, being more like the all-season tires, come in a wide variety of stock finishes.
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