Sunday, January 05, 2014

Ores for Bloomery Iron Smelting?


Forum: Bloomers and Buttons
=====================================
Topic: iron ore websites ( Steven S.)
http://www.bladesmithsforum.com/index.php?showtopic=28350
............................................
I've been looking around the internet for sites that sell raw ore but all I can find is mines for sale or large quantities (tons or more). 
if anyone could point me in the right direction to smaller amounts that would be awesome.
First - a basic overview

Finding a natural ore depends on geography, and as 'plentiful' as iron oxide is in the environment (generally), truth is not *everyone* has access in their local area.

This normally means one of three possible commercial sources:
Industrial Taconite Pellets
Hematite Sandblasting Grit
Iron Oxide Pigment

Industrial Taconite will depend largely on industry in your area. This is the form iron is semi processed at the mine, then shipped to the smelter for modern steel production. If there are no mills (or mines!) in your area, sometimes this material can be found 'spilled' along transport routes - being harbours or rail lines.
Taconite will require roasting, then labourious breaking into smaller pieces for the typical small size bloomery furnace.

Hematite Sandblasting Grit comes from a source in Quebec, and is ground and bagged here in Southern Ontario by Opta Minerals. The modern use is for sandblasting large metal surfaces - primarily ship hulls for re-painting. The material may be available in 90 lb sacks. Check a local sand blasting company. Last time I could purchase the small size, it ran about $20 per bag.
Hematite Grit is tricky to use in our bloomery furnaces, as the smaller size particles tend to reduce quickly and absorb excess carbon. This can yield 'steely' blooms - but its also easy to end up running too hot and getting cast iron.

Fine Iron Oxide Pigment is used in two modern applications. It comes in 50 lb bags, used for glazes by potters, and to colour concrete. If you can find a concrete supplier that would sell a few bags, this is likely to be the most cost effective. (Mainly because the material is likely to be less refined - so cheaper.) Most pottery suppliers also have the material, better processed ($$) in three forms:
Black (Fe3O4), Red and Spanish Red (both Fe2O3). Avoid the more pure 'Red', which here in Ontario runs about $200 per bag (!!). Right now the higher iron content Black and lower iron purity Spanish Red are costing about $50 per bag.
My team here started working with these fine oxides a number of years back when we were trying to create a substitute for natural primary bog iron ore. The trick is to mix the fine powder into a paste with the addition of 10% whole wheat flour. The paste is then spread out and allow to dry and then broken into chunks. If you attempt to use the fine powder direct into the furnace - the air blast simply blows most of it right back out again.


Black Potter's Oxide - mixed to analog, ready for the furnace
Full Smelt Report - Vinland One

There is a lot of information available on this blog on the development of what we call 'DARC Dirt' Analog :

I've got a table up that compares the various ore types (that we have worked with here)


No comments:

Post a Comment