Fireweed Zinc Announces Positive Preliminary Economic Assessment with Pre-Tax IRR of 32% and NPV (8%) of C$779M on Macmillan Pass Project https://www.globenewswire.com/news-release/2018/05/23/1511189/0/en/Fireweed-Zinc-Announces-Positive-Preliminary-Economic-Assessment-with-Pre-Tax-IRR-of-32-and-NPV-8-of-C-779M-on-Macmillan-Pass-Project.html May 23, 2018 16:58 ET | Source: Fireweed Zinc Ltd.