Chemistry of manganese precipitation in Pinal Creek, Arizona, USA: A laboratory study

Characterization of Mn oxides in cemented streambed crusts from Pinal Creek, Arizona, U.S.A., and in hot-spring deposits from Yuno-Taki Falls, Hokkaido, Japan

“…Sample 1 was taken at Inspiration Dam and sample 2 about 5 km upstream at the beginning of Setka Ranch (cf., Fig. 1 in Hem and Lind 1994;Fig. 2 in Lind and Hem 1993).…”

“…Additional motivation for this investigation was provided by the results of some experiments by Hem and Lind (1994) who simulated precipitation from Pinal Creek stream water. They flushed Mn-rich, near-neutral ground water with CO 2 -free air while slowly adding base at 25 ∞C up to pH ~9 and then aged the suspension for about three months.…”

Rock varnish in New York: An accelerated snapshot of accretionary processes

“…Some of the first microscopic evidence of a biotic origin for Mn-rich coatings was found on stream-side rocks in a Queensland rainforest (Francis, 1921). A long tradition of basic and applied research on Mn-rich coatings in a wide variety of fluvial settings (Ball, 1903;Bhatt and Bhat, 1980;Blackwelder, 1948;Boussingault, 1882;Carpenter and Hayes, 1978;Carpenter and Hayes, 1980;Hem and Lind, 1994;Huelin et al, 2006;Hunt, 1954;Klute and Krasser, 1940;Potter, 1979;Robinson, 1981;Robinson, 1993;Tebo et al, 2005;Whalley et al, 1990Zahn, 1929 contrasts with the common textbook and Internet perception that rock (or desert) varnish is a dryland phenomenon.…”

Manganese and limestone interactions during mine water treatment

“…Although manganese carbonate would be expected in the presence of the anion, the formation of oxides is the rule. Even under those conditions where the water presented a significant concentration of carbonates, manganese oxides were suggested as the predominant species, favored by highly dissolved oxygen concentrations (forced aeration) as well as high pH [33], while carbonates were frequent only at high activities of dissolved carbon dioxide [15]. In this regard, when carbonate dissolution provided high calcium concentrations, kutnahorite (CaMn(CO 3 ) 2 ) was precipitated [4] as geochemical modeling predicts that some mine water would be supersaturated with respect to this mineral.…”

“…One of these species was kutnahorite, CaMn(CO 3 ) 2 , which is thermodynamically stable in such waters, provided Ca 2+ is available [4,15]. Due to the complexity of the different processes occurring during the passive treatment of [16], while nearly 90% of the manganese present in a carbonate precipitate from an AMD pond was in the form of oxides [15]. Seeking to shed new light on the role of limestone in manganese removal, the use of fine ground limestone powder as a cost-effective, simple alternative to remove manganese from mining-affected water was studied.…”