Content type browser - Materials
Start from scratch
Create a new material based on one of the default material types.
Import From File...
Import a Rhino material (*.rmtl) on the disk.
Custom
Create a new custom material.
Start from existing
Select an existing material as the template to start a new material.
Make a copy
Create a standalone material from the selected material.
Share all settings
Create a material instance from the selected material. The settings in the two materials are linked.
Show tree view
Display the tree structure of the existing render content items on the left.