A beautiful late Victorian oversized European style pillow sham or possibly a crib duvet cover. Possibly being used even for a Christening?  This elaborate cover could certainly been intended for special occasions.  The piece is made with a triangle in each of the four corners, three sets of tucks with whitework eyelet insertion.  Each of these area measure 14" H on the diagonal x 25-1/2" across the width   Entirely around the outside edge is a 3" ruffle, also in whitework eyelet.  

The cover has a backing with buttonholes on both sides of the opening. The fasteners would take a shank style but no fasteners were found with the sham. 

Just thinking, I wonder if button holes on the one side could be stitch closed with regular buttons attached.   A little work but could be done....or perhaps just leave the back open with no fasteners. Wonderful soft white cotton fabric of nice quality. 

The size of this beauty is 43" x 47".   So perhaps think out of the box and come up with your own creative way of accenting your decor... for instance, maybe draped over a bench at the foot of a bed? 

Condition:  Missing the fasteners. I noticed one pin hole and a small shred to the fabric at one of the triangle areas. (see photo).  The largest is 1/2" in length and could be mended.  Although not recently laundered, it is clean.