Primitive Technology: Making Iron From Creek Sand

By | October 31, 2022

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

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