Let ,
 
, and 
 be tetrahedra in projective three-space 
. Then the tetrahedra are said to be desmically related if
 there exist constants 
,
 
, and 
 such that
A desmic surface is then defined as a quartic surface which can be written as
for desmically related tetrahedra , 
, and 
. Desmic surfaces have 12 ordinary
 double points, which are the vertices of three tetrahedra in three-space (Hunt
 1996).
 
         
	    
	
    
