Yes, what Stu posted is a good illustration. What happens as the the wood goes from the root to the trunk it turns outwards because the the tree is thicker at the base than the center.

Now look at Stu's "slab cut" picture and imagine, when you go from the tip of the blank to the butt the wood isn't going to be uniform because the grain in the tree is turning outwards because it's larger at the bottom and the growth are curved inside the blank. So, when the blank is turned what you see on the out side may not be on the inside where the finished stock is. This isn't always a bad thing but, you can't always look at a slab sawn blank and get an idea of what it's going to look like turned.

Here is the top view of a slab sawn piece of Turkish walnut. See how the grain is turning out out the wood as it goes down the blank? Like I said this isn't really a bad thing, but it's had to judge where the figure will fall when it's turned. We ca guess about where it'll be and how much because we can see all 4 sides. They aren't a mirror of the stock though.
[Linked Image]

Now for quarter sawn. Look how all the growth rings are uniforn. What you see on the outside of this blank is what it's going to look like on the inside when it's turned. This is because the grain is running the same direction as the blank. The down side for wood cutters and quarter sawn blanks is there is much waste and you don't get nearly as many as with a slab sawn tree. The plus side is these quarter sawn blanks are worth much more money.

Terry

Last edited by TC1; 09/15/09. Reason: added info