Why it matters
The most tangible candidate for lost engineering — sub-millimetre joints in hard stone. We hold the craft as real; 'lost machines' stays a clearly-labelled frontier.
What mainstream says
Small and medium work has been reproduced with stone tools and copper-plus-sand abrasive; the 'machined' vases lack provenance.
This is the frontier — where honest wonder ends and wishful thinking begins. Stand right on the line.
Graded Contested · C on the Ancient Code honesty scale (A grounded · C contested · S speculation · U unidentified). It belongs to the Impossible stone line of evidence.
Sources & further reading
The authoritative reference for this site/finding — and its own primary citations — so you can check us.