Three types of antique brass lamp and what each began as
Converted oil lamps are the most common. A brass font that once held paraffin or colza oil has been drilled for a cord, fitted with a socket and topped with a shade. Look for the original burner collar, often engraved with a maker's name, and for a filler hole; a conversion that kept these parts is more honest than one that removed them. The font should be heavy and seamless, or seamed vertically if spun in two halves.
Bouillotte lamps have a dished brass base, two or three candle arms and a tole shade, often painted dark green, that slides down a central rod as the candles burn; electrified versions keep the rod for adjusting the height. Student lamps, from the 1870s onward, have a brass reservoir on one side, an arm to the burner and a green or white glass shade. Each type has its own weak points: the rod and shade on a bouillotte, the arm joint on a student lamp, the socket conversion on an oil lamp.
Weight, patina and what plated brass looks like
Cast and spun brass is heavy for its size. A bouillotte base 10 in (25 cm) across should weigh 4 to 7 lb (2 to 3 kg) before the shade; a lamp that feels light is often plated steel, zinc alloy or brass-coated aluminum. A magnet settles the steel question. Plating wears through at the edges and shows a gray or copper-colored base metal; solid brass wears to a duller yellow and develops a brown patina rather than a different color.
Patina on brass is a choice, not a defect. The Canadian Conservation Institute's note on brass and copper explains that polishing removes metal each time and that a stable, even brown surface protects the lamp. Lacquered brass, common on 1920s to 1950s lamps, shows patchy brightness where the lacquer has failed; stripping and re-lacquering is a workshop job. Decide before buying whether you want a bright lamp or a mellow one, because reversing either choice costs money.
Rewiring an antique brass lamp to US standards
Assume every antique brass lamp needs rewiring. Old cords with cracked rubber or cloth insulation, brittle bakelite sockets and unpolarized plugs are fire and shock risks. A lamp restorer will fit a new cord rated for the lamp, a polarized or grounded plug, a socket with the shell insulated from the brass body and, where the body is metal and accessible, a grounded conductor. Ask for a lamp wired with UL-listed components and keep the receipt with the lamp's documentation.
Converted oil lamps need one more check: the cord path. A cord that exits through the base and lies flat under a felt pad is correct; a cord emerging from the side of the font with a sharp edge will chafe. Student lamps and bouillottes should keep their adjustable parts moving freely after rewiring, with the cord routed so the shade can still slide. Budget 1 to 3 hours of workshop time for a straightforward rewire; more if the socket cap must be fabricated.
Choosing a shade that fits
The shade governs the light. A rule that works for table lamps: shade diameter at the bottom equal to about two thirds of the lamp height, and shade height roughly one third of the total. A 24 in (61 cm) converted oil lamp takes a shade 14 to 16 in (36 to 41 cm) across. Fit the harp so the socket sits just above the shade's lower rim and no hardware shows at eye level when seated.
Bouillotte lamps keep their tole shade; a replacement should be the same diameter as the arms' spread plus 1 in (25 mm). Student lamps take a glass shade of the fitter size stamped on the gallery, commonly 7 in (178 mm). For converted oil lamps, linen, parchment or pleated silk suit a French country room; keep patterned shades for the children's room. A warm bulb of 2700 K and 40 to 60 W equivalent gives the light these lamps were made for.
What to compare
| Form | Suggested Use | Decisive Check |
|---|---|---|
| Converted brass oil lamp | Side table in a living room, bedside | Original burner collar; rewired socket and cord path |
| Bouillotte lamp with tole shade | Desk, console, library table | Rod and shade slide freely; weight of the base |
| Brass student lamp | Study desk, reading corner | Arm joint tight; correct glass shade fitter size |
Your buying checklist
Continue planning your room
Frequently asked questions
How do you know if an antique lamp is solid brass or plated?
Weigh it and use a magnet. Solid brass is heavy for its size and non-magnetic; plated steel attracts the magnet, and plated zinc or aluminum feels light. Look at worn edges: plating wears through to a gray or copper-colored base metal, while solid brass simply dulls to a browner yellow and stays the same color underneath.
Does an antique brass lamp have to be rewired?
Treat it as mandatory. Cords with cracked or cloth insulation, brittle sockets and unpolarized plugs are shock and fire risks. A restorer fits a new rated cord, a polarized or grounded plug and an insulated socket, using UL-listed parts, in one to three hours of workshop time. Keep the invoice with the lamp as part of its documentation.
Should you polish an antique brass lamp?
Only if you want a bright lamp and accept repeating the work. Polishing removes a thin layer of metal each time, and an even brown patina protects the brass. Lacquered lamps with patchy brightness need stripping and re-lacquering rather than polishing. Decide on bright or mellow before buying, because each choice is slow and costly to reverse.
What size shade suits a converted oil lamp?
Take the lamp height from base to the top of the socket and choose a shade about two thirds of that height in bottom diameter and one third in height. A 24 in (61 cm) lamp takes a shade 14 to 16 in (36 to 41 cm) across. Adjust the harp so the socket sits just above the shade's lower rim and no hardware shows at seated eye level.
Sources & further reading
- Canadian Conservation Institute — CCI Notes 9/3: The Cleaning, Polishing and Protective Waxing of Brass and Copper — Supports the advice on patina, the metal loss caused by repeated polishing, and the handling of lacquered brass.
- Canadian Conservation Institute — Care of metal objects — General care of metal objects: handling, humidity and avoiding abrasive cleaning.
