Blinds, Shades and Shutters - cleaning a lampshade

Hi Again,
One more problem - I have cleaned my fabric lampshades in the past but I tried cleaning this one I have never cleaned before and instead of cleaning it left ugly water/rusty- looking, swirl stains! Any idea how I can remove them and get them clean now, (the original idea!)??
I usually use a very mild detergent in warm water and dry outside in the sun, and never had a problem...
Reponses much appreciated!!!!
M

for cleaning lampshades i put warm water in the bathtub with a bit of bleach , turn the shade on it's side and roll it around so all material gets equal time in the bath. rinse well under the tap or shower head and let dry. place on a bottle or something so bottom does not touch anything

I have washed old lampshades as a last step before replacing them. I worked quickly by giving them a quick turn in sudsy water in one side of the kitchen sink and then spraying to rinse in the other sink. I immediately set them on a towel on the counter and blotted with soft cloth, paying particular attention to blot along the top and bottom hems. Then, once they were past dripping I placed them back on the lamps with the light on so the heat would finish drying them. The problem with this method is that most lamp shades are glued, and many have paper hems. Washing can actually cause the lampshade to fall apart, unless the hems are stitched. Work quickly to avoid having the lamp shade in the water too long.

Lampshades will yellow and discolor over time due to age, sunlight, gas, cigarette smoke, air pollution, and the baking in of dust and soil from the heat of the light. Frequent dusting with soft brush or brush attachment is important. Shades can be wiped with a dry sponge from the janitorial supply. The dry sponge acts like a giant eraser to remove dirt from nonwashable surfaces.