Mid Century acrylic abstract painting from the sale 1960's

Breath taking mini painting, abstract, mid century from an unknown artist
The tag its missing sale from the back and it's not signed
It's acrylic on metal with the cork base
It has some scratches but nonetheless absolutely beautiful
Measures 4 3/4 inches length x 4 inches wide and weights 5.3 oz.
colors are very nice, lovely contrast of black and white with purple and blue with a golden background