Found 22 Plain CC0 textures in library

Book Pattern
Brick Wall 001
Carpet 012
Carpet 013
Clay Floor 001
Concrete 030
Concrete 032
Concrete Floor 02
Concrete Floor Worn 001
Fabric 059
Fabric 060
Fabric Pattern 05
Fabric Pattern 07
Fine Grained Wood
Grey Plaster
Kitchen Wood
Wood 047
Wood 048
Wood 049
Wood 050
Wood 051
Wood 052