Vintage Kappa Sigma fraternity pledge pin and Kappa Phi Delta sterling pin

Both are vintage items.  The Kappa Sigma pin has a screw back and is not marked. The Kappa Phi Delta or Kappa Delta Phi pin is sterling silver with a black enamel on the larger pin. The smaller pin is attached to it via a chain and is engraved “SR”. The back is stamped with a mark and tests as sterling silver. The black enamel pin measures 5/8” x 9/16”, without the chained pin. There is some discoloration on the front of the pin. The Kappa Sigma pledge pin measures 3/8” x 3/8” and is in excellent condition.