Rare Modernistic Sterling Silver Clothing Buttons Set by William Spratling

Vintage matched set of 5 hand made 980 silver Mid-Century Modern clothing buttons. 980 silver has a higher silver content than 925 sterling silver. 
Made in Taxco, Mexico and hallmarked by William Spratling. 
Measure 1/2" square and 8 mm deep. 
Original patina and tarnish.
Weigh 29.9 grams as a set...each button being around 6 grams each. 
They are shank back and all shanks are present. Some still have pieces of old wool fabric attached. 
Very nice cube design.