How will the lampshade attached to the lamp?
Most lamps use a detachable, hoop-shaped, two piece lamp harp assembly to secure the lamp shade to the lamp. The lamp harp snaps into the lamp harp saddle (the u-shaped bracket immediately below the lamp socket).
The top of the lamp harp has a threaded finial post that fits through the lampshade washer on the lampshade ring. A decorative finial screws onto the lamp harp to secure the lamp shade.
Lamp harp - lampshade harp - lamp shade harp -- Gold Life Lighting Co., Ltd.