Vintage Tensor Pittsburgh Collection Halogen Dimmable Lamp, model LT627-12. It features a postmodern "UFO" or "space age" saucer-shaped shade. The lamp has an adjustable, articulated arm with three points of articulation. It uses a 50-watt halogen bulb and includes a rotary dimmer knob on the base. Original lightbulb included. Missing lampshade cover, but does not affect lighting. Gets hot so adjust while off.
I have had other replacement bulb for over 20 years for my desk lamp. The 100 watt bulb should give a natural very bright WHITE light when the rheostat is turned up fully. With this bulb a non-bright yellow light was all that was emitted. I will guess somewhere between an incandescent 50-75 watt bulb output.