Hello Anne.
It depends upon the type of lamp that is inside the pendants.
Are they standard "A lamps"?
The kind of bulb you would put into a table lamp?
Are they halogen? LED? CF?
Lighting design is dependent upon the actual output of light from the light source.
This insures that you will have adequate illumination, as well as a pleasing aesthetic.

~Lynn

Be careful what type bulb you put in your pendants. We just redid our kitchen and the contractor put in some incandescent bulbs (60W) and it was like standing in an Easy Bake Oven. Switched them out for LED's and light is great and you don't feel like you in a tanning bed.

I am looking at using the Galeana seeded glass mini pendant, which I found on Houzz, I am not sure about what light bulbs goes in there. I will have to check it out

Image below, says a 100 watt bulb, so I am guessing two should suffice?