https://pubs.usgs.gov/of/2018/1021/ofr20181021.pdf
Summary of the Proposed Draft List
Based on an analysis using multiple criteria explained below, 35 minerals or mineral material groups have been identified that are currently (February 2018) considered critical. These include the following: aluminum (bauxite), antimony, arsenic, barite, beryllium, bismuth, cesium, chromium, cobalt, fluorspar, gallium, germanium, graphite (natural), hafnium, helium, indium, lithium, magnesium, manganese, niobium, platinum group metals, potash, rare earth elements group, rhenium, rubidium, scandium, strontium, tantalum, tellurium, tin, titanium, tungsten, uranium, vanadium, and zirconium. The categorization of minerals as critical may change during the course of the review process and is thus provisional.
"The platinum group elements include platinum, palladium, rhodium, ruthenium, and iridium."
from the past..
Toronto, Ontario, December 8, 2009. Noront Resources Ltd. (“Noront” or the “Company”) (TSX Venture: NOT) is pleased to report that check assays of hole 09-070-W1 at the Company’s Eagle’s Nest deposit, at the McFaulds Lake Property, confirm the impressive platinum and palladium grades originally reported on November 19, 2009. More interestingly, the high grade platinum and palladium grades triggered internal quality controls which included assaying samples with both platinum and palladium results exceeding 10.0 gpt for rhodium. Preliminary rhodium results indicate grades in excess of 2.0 grams per tonne associated with the higher-grade platinum and palladium samples. In light of the preliminary results which strongly suggest the presence of additional platinum group elements, specifically, rhodium, iridium, osmium, ruthenium and rhenium;
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"Other major mineral commodities such as gold, lead, zinc, nickel, and iron also are important potential sources for byproduct critical mineral production. A strategy for addressing the special characteristics of byproduct mineral supply needs to be an important part of the report submitted on implementation of the EO. Additional discussion of byproduct mineral commodities is included in appendix 1."
