[Rockhounds] North Dakota's Fire-Formed Rocks (and an apology for the last post)

[Paul]

By the way, I apologize for my lat post. It was meant for a different 
mailing list.

John Bluemle,, 2015.6-North Dakota's Fire-Formed Rocks
Published May 20, 2015 | By http://johnbluemle.com
http://johnbluemle.com/2-clinker-in-western-north-dakota/

Estes, M.B., Ritterbush, L.W. and Nicolaysen, K., 2010. Clinker,
pumice, scoria, or paralava? Vesicular artifacts of the lower
Missouri basin. Plains Anthropologist, 55(213), pp.67-81.
https://krex.k-state.edu/dspace/bitstream/handle/2097/15693/RitterbushPlainsAnth2010.pdf
https://krex.k-state.edu/dspace/discover

Gonzalez, M.A., 2009. Badlands of the Northern Great Plains:
Hell with the Fires Out. In Geomorphological Landscapes of the
 ??World (pp. 29-38). Springer, Dordrecht.
https://www.researchgate.net/publication/259597859_Badlands_of_the_Northern_Great_Plains_Hell_with_the_Fires_Burned_Out
https://www.researchgate.net/profile/Mark_Gonzalez

Heffern, E.L. and Coates, D.A., 2004. Geologic history of natural coal-bed
fires, Powder River basin, USA. International Journal of Coal Geology, 
59(1-2), pp.25-47.
https://www.sciencedirect.com/science/article/abs/pii/S0166516204000126

Quintero, J.A., Candela, S.A., R??os, C.A., Montes, C. and Uribe,
C., 2009. Spontaneous combustion of the upper paleocene
cerrej??n formation coal and generation of clinker in la guajira
 ??peninsula (Caribbean region of Colombia). International Journal
of Coal Geology, 80(3-4), pp.196-210.
https://repository.si.edu/bitstream/handle/10088/15941/stri_Quintero_et_al_2009.pdf?sequence=1&isAllowed=y

Yours,

Paul H.