In the January 2012 edition of the Financial Times' How To Spend It magazine, there is an article called The New Bronze Age -- bronze "...adds richness without overpowering, and sits equally well with antique and contemporary pieces...bronze is the metal of the moment". And, from a lighting perspective, we would endorse this. So that's the first thing you need to know!
The second is that, as far as lighting is concerned, "bronze" tends to describe a finish: the article itself may be made of brass or steel. But, to complicate things, there is little agreement about what a "bronze" finish actually looks like -- what colour it is. So, if you are specifying something in bronze be afraid -- be very afraid! Make sure that you have seen a sample.
This is particularly a problem if you are American and the light is European, or vice versa. The image at the top of this post is of a wonderful Altar from Alabama-based Kevin Reilly. It is illustrated in the finish in which most of his pieces are shown:
Europeans automatically assume that this is bronze. But here are tiles in four of his finishes:
The finish most often used is actually "Dark" (steel dark patina") whereas "Bronze" (steel bronze patina) is paler, yellower.
The fine lighting company most committed to bronze is Objet Insolite. Their showrooms are in Paris, but the work is done in their workshops in Normandy. This is their standard finish:
Objet Insolite Grande Clara
They really are working in bronze. After the item has been cast:
it is finished. Here, the standard finish is being created, using heat and oxidization:
But they can also apply electrolytically a nickel or gold finish (and, formerly, a wonderful verdigris).
So, having learnt that bronze lights are not often bronze -- they are brass or steel with a bronze finish -- the next thing you need to know is that not all bronze lights look bronze! They could have a nickel or gold finish. For example:
Objet Insolite Luxor
Objet Insolite Mostra
The effect of having cast bronze as the base is to make the gold and silver much gentler, much softer, removing any possible bling effect. This is one consequence of the method of finishing: the surface is not smooth, the edges are not machined, and the shape can have a hand-made feel, which is, again, much softer than gold or chrome/nickel on a crisp brass or steel base. It is like a pencil sketch compared to a CAD drawing. I hope that you can see this in the big picture of Clara above.
Bronze is often spoken of in the same breath as weathered brass, and so adopts a seaside/lantern/outdoor feel (even if they are for indoor use only).
Here is a bronze ceiling light from Nautic:
Nautic Village ceiling light
But here are weathered brass lights from the same source. The very elegant restrained Ilford small wall lantern:
Blakes, a battery/LED cordless outdoor table light:
Or Portreath, an indoor rectangular pendant.
So brass with a weathered finish is in many ways able to be treated like bronze, making available a far wider choice of designs, and lower price points.
One of the oldest and finest French metal-working companies is Pouenat Ferronnier. They use bronze finishes on brass, a dark antique bronze as in the hammered structure of L180 from the collection designed for them by Michel Jouannet:
and a light antique bronze. But they are also working in other metals -- steel and wrought iron. The latter can give the same handmade, rounded feel as bronze, while still conveying the brute strength of iron, as can be seen in A1-1 from the same collection...
...a gorgeous, massive handmade nail against a back plate of alabaster. During Maison & Objet, they introduced a new collection designed for them by Jean-Louis Deniot, whose bronze fireplace was featured in the How To Spend It article. No pictures are available yet.
Finally, lest you think bronze is all about the bucolic, the rustic, Jean-Luc Le Deun, who has been working with LEDs since 1997 (so longer than just about anybody else in decorative lighting) and is using them in the most minimal, elegant, geometric pieces like this chandelier:
announced at Maison & Objet last month that he is introducing a bronze finish! The first design to which it is applied is the Micro Prestige table light: