This is bohemian / czechoslovakian hand cut crystal.   As far as I have researched it is the base of a lamp.  It has what appears to be czechoslovakia embossed on the glass.   Its difficult to photograph.   There are no chips or cracks.  There is a hole through the centre of the glass as well as an indentation around for the rim, presumable for electric cable.    This is a heavy piece weighing 1.8 Kg.  The other piece with the electrical fitting came with the base but does not appear to belong to it.  It is also hand cut crystal.   I welcome comments and questions.