White powder in my washed Ethyl Acetate

After the CIELO process using fumaric acid I washed my EA with super washing soda and water per the instructions and put it on a mag stirrer for a few hours before filtering that solution into separate mason jar.

After about 10 days I looked at the reclaimed EA and noticed white powder at the bottom. I scraped off about 500mg. I then took a few milligrams and placed in small glass container and put a few drops of 5% white vinegar on it. There wasn’t any fizzing and the powder dissolved.

Is the powder mescaline fumarate?

I don’t have a marquis testing kit available.

Thanks!