Hollow forms look like a vase but are not intended to hold water and flowers. They can be treated so they can but it is not a common practice. These pieces get their shapes from ancient Far east, Middle East and Native American cultures to name a few. Hollow forms are one of the most difficult types of woodturning. There is always risk when trying to create a thin even wall thickness. The problem is you can't see where you are hollowing. I have made a few fancy funnels! This happens when the inside is larger than the outside. Oops! They are hollowed out using specialized tooling for getting around corners and deep into the vessel. I turn these pieces while the wood is green and when they dry, that thin even wall thickness I strive for will help alleviate distortion. In some cases this distortion is very attractive.
Sweet Gum Hollow Form, Tunge Oil finish, 3" x 8"
Modesto Ash Hollow Form, Tunge Oil finish, 7" x 4"
Modesto Ash Hollow Form, Tunge Oil finish, 5" x 4"