I'd posted a question last week about metallic thread. Another member mentioned Glitter Thread from Superior Threads but had used it on an art quilt so wasn't sure if it would stain the fabric after getting wet. I sent an email to Superior Threads and this is the reply I got from them. Here's the link if you'd like to take a look at it.
http://www.superiorthreads.com/product/brand/glitter/
"Good morning Kimberly,
Thank you for your inquiry on our glitter threads. Although our Glitter thread is a flat metallized thread, it is not considered a Metallic in the way it is manufactured. Glitter is more like the composition of a Mylar balloon and it is guaranteed to be color-fast.
Just a side note, our Metallics are made differently than other metallic threads and are also guaranteed to be color-fast, as long as they are laundered as instructed in our washing guide.
We hope this information is helpful. Thank you for allowing us to serve you in your quilting needs. Please let us know if you have any other questions, we'd love to help.
Have a superior day!
Melanie McElroy
Superior Threads
435-652-1867"