Possibly this could be included in the FAQs?
Pattern Welded shotgun barrels can be classified into three general categories, all starting with strips of iron and steel, but with different manufacturing methodology:
Twist -thin ribbons of layered iron and steel which were NOT twisted before being wrapped around the mandril and hammer forged.
http://docs.google.com/Doc?id=dfg2hmx7_40dxk2scc7
Crolle Damascus in many patterns which are determined by how the iron and steel were 'piled' or layered in the billet and the twisting of the rods.
http://docs.google.com/Doc?id=dfg2hmx7_163vgh5prdf
http://docs.google.com/Doc?id=dfg2hmx7_180c83rvwg4
Laminated Steel - a higher ratio of steel to iron mixed together and ‘puddled’ before being formed into rods.
http://docs.google.com/Doc?id=dfg2hmx7_52fs85cfgt
Damascus
quality is best judged based on the overall grade/quality of the gun, not the appearance of the Damascus pattern, the name given the barrels by the maker, or the country of origin.
See
http://docs.google.com/Doc?id=dfg2hmx7_22ddqshmdq
How do you 'read' crolle damascus?
http://docs.google.com/Doc?id=dfg2hmx7_0dgmfqfgm
http://docs.google.com/Doc?id=dfg2hmx7_8gmzs6hck