This Chinese Elm set was rough cored in 2007 5 years ago. Warping was considerable after 5 years but surprisingly enough, no cracking at all. The thickness of each rough turned bowl was the commonly used 10 % of the diameter of each. Even after voiding all of the moisture content, they remained considerably densely heavy and did not turn as easy as other woods I have cored. The bowls are finished with Mike Mahoneys Walnut Oil and Wax which really popped the grain. From the large bowl to the smallest, their sizes are 12 Dia. X 4, 9 Dia. X 2, 6.5 Dia. X 1.5 and 3.75 Dia. X .75.