I have an office set-up similar to your Mom's and I like a tall, buffet style lamp so that a wider area of the desk top is well lit. I have a lot of paper-work (DH self-employed) and I need a well-lit desk.

A true desk lamp provides good lighting, but on a smaller area.

One other suggestion - your picture doesn't show it, but is there a vertical piece near the desk or behind her back(file cabinet or bookshelf)? I have a 4-drawer file cabinet at the end of my desk and have found that a lamp on top of it allows more light to "flood" down on the desk area, plus it gives the whole room a nice glow.

I think a slightly taller lamp with a WHITE shade will give her more light...I have a buffet type lamp by my desk and it has a white shade...gives a nice glow over the desk.

A white shade is a must. I'm using a buffet lamp also, w/white shade. However, mine is a tad too short so I have it propped up on two books. 60w bulb, and it's perfect.

The one on dh's desk uses two 75 watt bulbs. It's from LL Bean.

Thanks all for the suggestions of the buffet lamp, I talked to her and she seems agreeable to try one out. She does have a file cabinet on the left side of the desk but doesn't want to move any papers. Hopefully one will be enough.

Great looking lamp there Natal, the colors are so pretty. Bet it looks lovely when lit.