Brian: (et All)

My experience on trudging through bogs is limited. A couple of days in 
Newfoundland. A lot more searching around middle Ontario without a lot 
of luck. A lot of talk about sources in Denmark with the smelting 
enthusiasts there.

Now, what I know about this I learned from Arne Espelund. The comments 
here are based on the physical geography of 'Mid North' Canada - which 
is likely much different than your situation in Ireland! Forgive me for 
this more practical advise, this will certainly not be given in the 
language of geologists.

In Newfoundland (and on the Canadian Shield in the Mid North) the 
organic top layer is relatively thin.  The bog ore accumulates in the 
boundary between this top organic layer, and the sterile sub soil 
underneath. In the places I have searched, the boundary was from 12 - 18 
inches down from the surface.
First thing to look for here is a chain of iron bearing rock with 
shallow upland bog pools over it. Then you find a small stream that 
empties out one of those bogs, ideally with enough drop in elevation 
that there is a 'babbling brook' kind of effect to tumble the water 
(introducing more oxygen). Then what you do is reach down along the edge 
of the bank, where the water has eroded the top vegetation layer away. 
If you run your hand along the boundary line, you can feel lumps of the 
accumulated bog ore. The stuff feels about the consistency of a hard 
window putty, or quite hard clay. At first you think its gravel, but it 
does not cut into your hands. The pieces I have gathered from sizes 
ranging from about pea size to some about the size of a dog turd. The 
amount of ore accumulated along a given bog and stream combination 
varies significantly. One stream I followed had only small traces over a 
kilometre of checking - then in one section of about 10 metres I found 
enough to gather two 20 litre pails worth in about twenty minutes.

There is no doubt that this is just one of several types of deposited 
primary bog iron ores. I did find a small amount of a form of 'lake ore' 
along the margins of larger bog pools down at the southern end of 
Newfoundland as well. This is maybe more like the stuff that you might 
find in Ireland?
One note of caution here! I was on my own, and at one point lost my 
balance while leaning over on hands and knees at the edge of a pool. I 
put my arm out to catch myself - only to find my hand quite rapidly 
sinking down into the goo. With images of Ancient Irish 'Bog People' 
flashing through my mind, I gave a massive jerk to throw my body back 
away from the water (at my chin by that point). Obviously I didn't end 
up a discovery for some future archaeologist, but it was a near thing. I 
keep to stream deposits now.

One other tip (blame Arne). You can roughly check the relative purity of 
the bog ore in the field - by eating it! Take a small (half pea) size 
piece and put it in your mouth. As it dissolves, the iron oxide 
component will turn into a fine powder and wash into your spit. The 
organics (like bits of grass) and most importantly the silica, as sand, 
will remain. By comparing how much sand is left from the starting lump, 
you get at least a rough idea how 'pure' the sample is. Not perfect to 
be sure, but good enough to keep you from hauling out kilograms of ore 
that later proves to be mostly sand.

You might also be interested in our work here to develop a bog ore 
analog. We are mixing powdered potters iron oxides with sand and flour 
(as a binder) to create a good working material. We have been able to 
match our mixes to roughly duplicate specific natural primary bog iron 
ores. (Our focus is the Viking Age smelt at L'Anse aux Meadows, but we 
are working some 3000 km away in Central Ontario.)
http://www.warehamforge.ca/ironsmelting/ores.html

-- 

****************************************

Darrell Markewitz - Artisan Blacksmith
the Wareham Forge - Historic Reproductions & Architectural Forgings
Interpretive Program Design - Specialist in the Viking Age
general information via e-mail - contact: [log in to unmask]

website :  http://www.warehamforge.ca
Blog : http://warehamforgeblog.blogspot.com

Author of:
Introduction to Blacksmithing (DVD)
Historic Bladesmithing (DVD)
Forging the Viking Age (DVD)
Experimental Iron Smelting from the Viking Age (CD-ROM)
Exploring the Viking Age in Denmark (data DVD)
all available at http://www.warehamforge.ca/video.html

All materials created by Darrell Markewitz copyrighted the author.
http://www.warehamforge.ca/copy.html