"TIL In the UK, the distinction between an actor and an extra is defined by agreements between the actors trade unions and the various commercial production bodies. These state that once a performer says 13 or more words in any scene, they must become a contracted actor in that production."
from Wikipedia
Amount of elements by percentage
Part examined
Copper Tin Lead Iron Sulfur Arsenic
Blade 80.3 18.8 0.4 0.4 trace trace
Yellow pattern 83.1 15.2 0.8 0.8 trace trace
Dark pattern 73.9 22.8 1.4 1.8 trace trace
Darkest regions 68.2 29.1 0.9 1.2 0.5 trace
Edge 57.3 29.6 8.7 3.4 0.9 trace
Central ridge 41.5 42.6 6.1 3.7 5.9 trace