Sinker means logs that sank and were submerged before reaching a sawmill. This wood is “sinker” Mahogany from Belize. It was under water for between 75 and 150 years before modern recovery methods allowed its salvage. As it dried minerals in the river water stiffened the wood. Some experts say the tone of the wood is crisper with more clarity to the tone. For more information go to YouTube.com/watch?v=OE1mHdXSfwk