Base and the shade are about 5 in diam. Chimney is clear glass rough cut on the top and bottom. Tiny flea bites on the bottom of the chimney. Burner is marked P&A Co.
Thumb wheel turns but doesn't move the wick. The top of the shade has what might be miniscule nicks.
Just mentioned because it is hard to determine if real or part of the cut. The item "Victorian RUBY SATIN GLASS miniature OIL LAMP 7 3/4 P&A Co. Burner" is in sale since Thursday, June 7, 2018.This item is in the category "Antiques\Decorative Arts\Lamps". The seller is "milkcrk" and is located in Portland, Oregon. This item can be shipped worldwide.