Pure heaven describes this gorgeous offering. A silk "Brick" is a very thick "top" available in short dense top form the mills fold up many times appearing to look like this gorgeous white brick, until it's unfolded, dyed and offered to you.
I dye them and leave them in their original length so the prices vary slightly, depending.
Mulberry/Bombyx Silk Bricks are used spinning as is, many love mixing it into their batts, or processing. I have had a lot of alpaca owners use it when they get their fleeces process because the fiber length is very long. Felter love using it in various art forms they are creating with, whether it's needle felted into a piece, inserted, or embedded. The long length means much less fuzz/pilling.
Mulberry - the Bombyx Silk Worm eats the Mulberry leaves, spins their lustrous cocoons, and over the past 20ish years what was standard to call Bombyx Silk has drifted every so slightly to be called Mulberry - the end fiber is the same.
And, the silk takes dye brilliants.
When spinning, gently pull off a few fibers, measure the length, and make sure your hands are about 2" further apart than that measurement to allow you draft easily. If you find you are tugging to draft - your hands are too close together.
Louie sez to relax and enjoy it because his momma sure does.