Sturdy, dense wood that should not float.
Premium pieces are especially attractive specimens with unique qualities often sought after by aquascapers
I ordered around 8 pieces total I believe. All of them were great quality and each had a unique characteristic. If you can afford it, I would definitely suggest splurging on a couple pieces of premium. While not necessary for everyone, I liked the extra intricate detail the premium offered. Really made the look I was going for. And in the grand scheme of things, a little extra cost to take it that one step further, was worth it.