Gorgeous tile!  I've been hoping to find a project for these but just haven't.

Have a glossy oily look 

Marked HT on that back

Dated 1978

49 tiles with no chips

12 tiles with chips (mostly small corner chips) 

5 7/8" square 

1/4" thick 

Salvaged tiles so have some grout on backs

Little bit scratching to faces from storage