A method 1, in which heating the final mixture is to {HEAD ~ a temperature} of {TAIL ~ 1550° 1700° C.}, after pressing thereof to a pressure of at least 35 MPa, to make a unitary artefact 
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A method 1 , in which heating the final mixture is to { HEAD ~ a temperature } of { TAIL ~ 1550 ° 1700 ° C. } , after pressing thereof to a pressure of at least 35 MPa , to make a unitary artefact
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH