At the main base...
Spare roof tiles from making the hut
The iron knife made from iron bacteria
Carving grooves into the roof tile
The roof tile will become a sluice box to separate the iron bearing component from river sand
The grooves act as riffles in the sluice that trap heavier iron oxide particles (magnetite) while allowing the lighter sand (silica) to wash away
Finished sluice box
At the river...
Placing the sluice in the water so the current runs through it (from wide to narrow end)
Ordinary sand from the river bank
This can be found in creeks and rivers everywhere
Putting the sand in the upper portion of the sluice to wash the silica sand and mud away while retaining the iron sand
Tipping the water and iron sand into the pot
See how the sluice works close up
The heavier magnetite component of the sand is retained in the grooves of the tiles
After sluicing once the sand is bluish grey indicating a higher iron content
A lot of sand needs to be processed to obtain the concentrated ore and this can take many hours
Note that some iron escapes in the tailings not far from the end of the sluice (bluish grey sand in the yellow sand)
Run it back through again so it's not wasted
The sand that's been sluiced once
Now sluicing that sand a second time to concentrate it even further
Observe how the heavier sand grains stay in the grooves while the lighter sand washes away
Once sluiced sand on the left, twice sluiced sand on the right. The twice sluiced sand is finer and more concentrated
After much work the concentrated iron sand is ready to test
Digging a pit to mix clay
Digging clay from the creek
Clay into mixing pit
Making a air pipe for the smelting furnace (tuyere)
Drying tuyere
Digging a furnace hearth
Lining with clay to form a bowl hearth (25 cm wide, 12.5 cm deep)
Tuyere penetrates 2.5 cm from inner wall, 15 degrees down from horizontal
Making walls of furnace, 25 cm inner diameter at base tapering to about 15 cm at the top. 37.5 cm tall from the tuyere height, 50 cm tall in total from the bottom of the pit
Dry firing the furnace
Centrifugal blower spun using a bark fiber cord thusly
Connecting blower to furnace
The tile roof protects the furnace from the rain while not burning down
Making charcoal in the now empty clay mixing pit
Making more rope to use on the blower
Extinguishing the coals with water
Charcoal ready to use in the furnace
Sluiced sand (iron ore)
Charcoal (fuel)
Smelt preparations complete
One hour pre heat with wood
Filling the furnace with charcoal
3 single handfuls of iron sand
After 5 minutes 3 double handfuls of charcoal, 3 single handfuls of ore
After 6 charges of charcoal and ore the furnace was fired till the material burnt down to tuyere level and it was doused with water
The slag and iron mass
On the outside we see a small iron prill
More iron prills
Crushing slag to find more
A few melted together
You can tell what is iron and what is slag by crushing it, slag crushes easily but iron doesn't
Proof of concept that iron can be smelted from ordinary river sand