Experimental Bloomery Iron Smelting DATA
101 tests from 2001-2025
Darrell Markewitz & Neil Peterson

The raw data gathered and prepared for :

'20 Years Before the Blast'
Experimental Bloomery Iron Smelting 2001- 2024
Experimental Bloomery Iron Smelting - Part Two

 Made available here to assist the work of other researchers *

Data Tables prepared by Neil Peterson

This chart displays all the variables charted
Furnace Types
 Describes the various furnaces used, measured details
Air Systems
 Describes the various air systems used, measured details
Burn Rates
 Lists the burn rates against sources and volumes
Ore Types
 Describes the ores used, amounts against yields
Ore Details
 GIves elemental contents of ores (figures used in calculations)
Calculations
 Showing calcuations used for areas, volumes, elemental contents
Working Teams Lists those participating, test locations and dates
Totals
 Some figures compiling totals of materials, blooms, time
Smelt 2 Smelt 2
'20 Years Before the Blast'
Experimental Bloomery Iron Smelting
2001 - 2024
with Neil Peterson

This 212 page volume is a survey of 101 iron smelting tests by the author and his working team, presented in a more formal academic style. Includes assesments of furnace builds, air systems, ore types and bloom qualities. There are overviews of four major experimental series; iron smelt in Vinland, Icelandic turf walled furnaces, the Turf to Tools project, and Norse Bellows equipment.
8 1/2 x 11 paperback format, 99 colour colour photographs, 25 illustrations, 48 charts and graphs.
companion to 'Basics of Bloomery Iron Smelting'

Kindle Edition
Amazon Paperback

Works by D. Markewitz referenced in the text

• 2005, ‘The EconoNorse Iron Smelter’, course handout

Also 2011, online (web site) : https://www.warehamforge.ca/ironsmelting/EconoNorse/index.html

• from 2006, ‘Experimental Iron Smelting’, online (web site) : https://www.warehamforge.ca/ironsmelting/index.html

• 2007, ‘Revised Air Delivery Test’, online (web site) : http://www.warehamforge.ca/ironsmelting/bellowstest.html

• 2007, revised 2012, ‘Air Flow Rates’, online (web site) :
http://www.warehamforge.ca/ironsmelting/flowrates.html

• 2008, ‘Towards an Icelandic Smelt - Based on the remains at Hals’, online (web site) : https://www.warehamforge.ca/ironsmelting/HALS/index.html

• 2012, 'But If You Don't Get Any IRON...' Towards an Effective Method for Small Iron Smelting Furnaces', in The EXARC Journal, issue 2012/1, online (web journal) : https://exarc.net/ark:/88735/10041

Also available as PDF : 
http://www.warehamforge.ca/ironsmelting/Get-Iron.pdf

• 2012 B, ‘Forging (a copper tuyere)’, online (blog posting) : https://warehamforgeblog.blogspot.com/2012/04/forging.html

• 2012 C, ‘Slag Tuyere Rings’, online (blog posting) : https://warehamforgeblog.blogspot.com/2012/04/slag-tuyere-rings.html

• 2014, ‘An Iron Smelt in Vinland - Converting Archaeological Evidence to Practical Method’, in Can These Bones Come to Life?, Cramer, M. (editor), Freelance Academy Press.

Version available as PDF : https://www.warehamforge.ca/ironsmelting/LAM/Smelting-Vinland-V3.pdf

• 2021, ‘Standardized Reporting of Experimental Iron Smelting - A modest (?) Proposal’ in The EXARC Journal, issue 2021/1, online (web journal) : https://exarc.net/ark:/88735/10559

• 2021 B, ‘Wind and Weathering – Part Two : Wind’, online (web site) : https://www.warehamforge.ca/ironsmelting/iron2021/10-30-21/wind.html

• 2021 C, ‘Pulsing Air – Equipment Test’, online (web site) : https://www.warehamforge.ca/ironsmelting/iron2023/10-23/index.html

• 2024, ‘Iron Smelting in Vinland’, Kindle / Amazon, the Wareham Forge

• 2024 B, ‘Turf to Tools – a Final Summation’, Kindle / Amazon, the Wareham Forge

• 2025, ‘Basics of Bloomery Iron Smelting’, Kindle / Amazon, the Wareham Forge


With Neil Peterson

• 2024, ‘How Dense Are You? Recording Bloom Density from experimental iron smelting’, Kindle / Amazon, the Wareham Forge

• 2024 B, ‘Icelandic Sod Walled Bloomery Furnaces – based on the remains from Hals’, Kindle / Amazon, the Wareham Forge

• 2025, ‘Experimental Bloomery Iron Smelting – Data’, online (web site) : https://www.warehamforge.ca/ironsmelting/Iron-Smelt-Data/index.html


Other Works of Relevance

• from 2006, 'Hammered Out Bits', online (blog) Search topic or label 'iron smelting' : https://warehamforgeblog.blogspot.com/

• 2006, ‘Continuing Adventures in Early Iron Production - An overview of experimental iron smelts,
2001 – 2006’, for Friends of the Medieval Studies Society of the Royal Ontario Museum 1st Annual Symposium. (unpublished)

2008, revised version available online (web site) : https://www.warehamforge.ca/ROMiron/V2/V2.html

• 2010, ‘Concerning the Shape of Blooms’, online (web site) : https://www.warehamforge.ca/ironsmelting/bloom-shape.html

• 2020, ‘Westward Viking – Iron from Norway to Iceland ... to Vinland’, presentation for the Woodford Furnace Festival, online (YouTube video) : https://www.youtube.com/watch?v=BfUzfGHuq7Q

• 2021, ‘Evidence of Absence, Erosion of Bloomery Furnaces’, online (web site) : https://www.warehamforge.ca/ironsmelting/erosion/erosion2021.html

• 2021 B, ‘Stacking Up, On constructing clay furnace walls’ online (web site) : https://www.warehamforge.ca/ironsmelting/stacks/stacks.html

• 2022, 'That Which Remains' : Signs from Bloomery Iron Smelting - Initial Compaction’, online (as PDF) : https://www.warehamforge.ca/ironsmelting/iron2022/2-compacting.pdf


with Smith, K. P., & Peterson, N., 2021, ‘Now with 70% Less Clay! Experiments with Viking Age Icelandic Turf walled Iron Smelting Furnaces’, presentation for the EAC12 Conference, online (YouTube video) : https://youtu.be/7Ltz5NG2BP0

with Cogswell, R., and Peterson, N., 2021, ‘Archaeology, Experience and Experiment : Further tests of Icelandic iron smelting furnaces’, in Can These Bones Come to Life? Volume 3, Cramer, M. (editor), Freelance Academy Press, (pending)

Revised version available online (web site) : https://www.warehamforge.ca/ironsmelting/iron2021/A,E&I-full/index.html


Related Publications from Darrell Markewitz

smelting 1
 smelting 1
Basics of Bloomery
Iron Smelting
Experimental Bloomery Iron Smelting - Part One
with Neil Peterson

ISBN : 978-1-0691597-2-4
January 2025

This 202 page book is a practical description of the bloomery iron smelting method, as well as providing a overview of the history and the theoretical process. There is information on ores, furnace construction, tools, operating sequence and the final bloom to bar step. Based on 20 years and 100 experimental smelts, with 115 illustrations and images. (8.5 x 11", colour)

Kindle Edition
Amazon Paperback
icelandic icelandic

Icelandic Sod Walled

Bloomery Furnaces

based on the remains at Hαls


ISBN : 978-1-0691597-0-0
December 2024
Prepared with the assistance of Neil Peterson

This 124 page report details 11 experimental bloomery iron smelts, running from 2001 to 2022, all based on aspects of the first iron smelt in North America, at L'Anse aux Meadows, Newfoundland about 1000 AD. Includes an analysis of the archaeological evidence, descriptions of the individual exerimental tests, with 44 images and 13 illustrations. (8.5 x 11", colour)

Kindle Edition
Amazon Paperback
Vinland Vinland
Iron Smelting in Vinland
Converting archaeological evidence to a practical method

ISBN : 978-0-9783284-7-4
November 2024

This 90 page report details 14 experimental bloomery iron smelts, running from 2001 to 2022, all based on aspects of the first iron smelt in North America, at L'Anse aux Meadows, Newfoundland about 1000 AD. Includes an analysis of the archaeological evidence and 49 images and figures. (8.5 x 11", colour)

Kindle Edition
Amazon Paperback
dense dense B
How Dense Are You?
Recording Bloom Density
from experimental iron smelting
with Neil Peterson

ISBN : 978-0-9783284-6-7
February 2024

This 46 page report details 30 iron blooms, all made during during investigations into Viking Age smelting methods, and compares them to a number of artifact blooms from Norway. Potential effects of ore types, air volumes, compaction efforts, and working experience is charted. (8.5 x 11", B&W)
T2T t2T b
Turf to Tools
A Final Summation
with commentary by Deirdre O’Mahony

ISBN : 979-83215146-1-0   
April 2024

A richly illustrated 76 page report on the Turf to Tools project, from 2013 - 23 at the Scottish Sculpture Workshop and the Wareham Forge. The project combined archaeology, practical experience, and artistic elements over 8 individual bloomery iron smelts and object creation. (8.5 x 11, colour)

Kindle Edition
Amazon Paperback

  Unless otherwise indicated :
All text and photographs © Darrell Markewitz, the Wareham Forge
 * The data presented here is drawn from records made during the bloomery iron smelts personally undertaken by Darrell Markewitz from 2001 to 2024, including 40 with the assistance of members of the Dark Ages Recreation Company. These data tables were prepared by Neil Peterson.
   These are being made freely available to other researchers in the hopes that they may assist in further evaluations of this work. Normal academic referencing applies.

   Please cite :
   - this web site : Markewitz, D. & Peterson, N., 2025, 'Bloomery Iron Iron Smelting Data', online (web site) : https://www.warehamforge.ca/ironsmelting/Iron-Smelt-Data/index.html
   - the published overview : Markewitz, D. & Peterson, N., 2025, ' '20 Years Before the Blast' Experimental Bloomery Iron Smelting 2001-2024', Kindle/Amazon, the Wareham Forge.
   - the individual reports : Markewitz, D., from 2006, 'Experimental Iron Smelting', online (web site) : https://www.warehamforge.ca/ironsmelting/index.html