Answer:
We have seen aqueous mackinawite slurry ( ca . 10% FeS) sell for about $3.50 to $4.00/USG (and that’s buying 90% water and other inactive ingredients!), and we have seen sulfidated ZVI sell for about $3 to >$15/lb. Comparatively, our select ZVI materials (see
ZVI tech sheet ) cost between $0.40 to $0.80/lb (micro ZVI costs more), and our other remedial amendments are very competitively priced.
Here, it is important to know that we have been adding sulfite and/or dithionite to our ISCR amendments for over a decade. And our unique ISCO amendments use iron activation chemistries. In both cases, these chemistries facilitate the formation of sulfidated iron complexes in situ – for free – and where you actually want them. See
Free Mackinawite and Sulfidated ZVI Tech Sheet for further insight into the true value and (long term) benefits associated with the purchase of mackinawite.