Silk blankets are often used in the item of home furnishings, so how to clean it has been the biggest issue for housewives.
One way is to wash it by machine. Set your washing machine on a gentle or delicate cycle with cool water setting for a large load. Add 1/4 capful of mild laundry soap per gallon of water. Place the silk blanket into the water and push down to submerge. Allow the washing machine to complete its washing and rinsing cycles. Place the blanket in the clothes dryer on a no-heat setting such as “Air Fluff” until dry. The time it takes to dry the blanket will depend on the size and weight of the item. Do not use heat to dry the blanket as it may shrink or dull the fabric.
For raw silk blankets, dry-cleaning is recommended for best results. But if you think it cost too much, proper machine washing is OK.