Stage 4
3hr.-3min.-1 sec.
Total time at the end of stage 4 = 8hrs.-41min.-23sec.
Screen size Material % found in this stage Grams Grams per minute (GPM)
1/2
basalt 
2.3g.
.01GPM
1/2
chert
2.0g.
.01GPM
1/4
basalt
17.7g.
.09GPM
1/4
chert
`1.2g.
.00GPM
w/s
basalt
51.0g.
.27GPM
w/s
chert
11.6g.
.06GPM
fines
combined
334.1g.
1.82GPM
Stage 5
2hrs.-31min.-28sec.
Grand total after stage 5 = 11hrs.- 12min. -51 sec.
Screen size Material % found in this stage Grams Grams per minute (GPM)
1/4
basalt
1.7g.
.01GPM
1/4
chert 
4.1g.
.01GPM
w/s
basalt
12.5g.
.10GPM
w/s
chert
5.0g.
.04GPM
fines
combined 
152.9g
1.24GPM
This is the point where the celt broke. The author estimates the celt would take approximately 10 to 12 hours of additional pecking and 4 or 5 hours of grinding, to complete the celt.
