Beautiful Vintage Crystal Vase - Shape inside Shape

This crystal vase and it's uniqueness & sparkle cannot be fully captured in pics. It has blown glass appearance but the top rim shows the elegant shaped & smoothed off crystal. The top four sides are wider in the middle (elegant shapes). Each of the four top sides are 4" long. As you may be able to see in pictures, The outside shape holds another shape inside - especially near bottom where round shows through sleek, sharp edges outside. EXCELLENT CONDITION! It measures 7.5" tall, 4" square at top, the thick base is 2.75" square, and it's approx 3.5" wide near middle