The CIM Mineral Resources and Mineral Reserves (MRMR) Committee develops and defines the standards, leading practices and guidelines that are intended to foster greater standardization of reporting within the public domain, specifically under NI 43-101. These standards provide a benchmark for both companies and Qualified Persons in discharging their responsibilities. CIM MRMR’s mandate includes maintaining and updating of the standards and guidelines, and to undertake a program of industry and CIM member consultation prior to submitting updates to CIM Council for approval.

The CIM Leading Practice Guidelines for Sedimentary Basin and Geothermal Brine-Hosted Lithium Mineral Resources and Mineral Reserves Estimation expands on the confined basin (salar-type) deposits covered by the 2012 CIM Best Practice Guidelines for Resource and Reserve Estimation for Lithium Brines.

The CIM Leading Practice Guidelines for Salar-Hosted Lithium Brine Mineral Resources and Mineral Reserves Estimation are intended for use with brines containing lithium and other valuable ions within relatively shallow, hydraulically-closed desert basins, commonly referred to as salars, salt lakes, salt flats or playas.

The CIM MRMR Committee has carried out a review and proposed update of these draft leading practice guidelines. The proposed changes reflect the current state of practice for estimating Mineral Resources and Mineral Reserves for lithium across all known deposit types, and other valuable metal ions in salar brine and confined basin (salar-type) deposits.

The CIM MRMR Committee is circulating a draft of the proposed changes and updates to both the CIM Leading Practice Guidelines for Sedimentary Basin and Geothermal Brine-Hosted Lithium MRMR, and the CIM Leading Practice Guidelines for Salar-Hosted Lithium Brine Mineral Resources and Mineral Reserves Estimation. The CIM MRMR Committee is soliciting public review and comment. Copies of both drafts of the proposed updated documents in Word format are available here for downloading and review.

Interested parties are invited to submit comments and suggestions by Friday, March 20, 2026.

How to submit comments:

Please note that you need a word processor (such as Microsoft Word) in order to proceed.

1. Click on the below links: 

   [Draft] CIM LP Guidelines for Salar-Hosted Lithium Brine MRMR Estimation

   [Draft] CIM LP Guidelines for Sedimentary Basin and Geothermal Brine-Hosted Lithium MRMR Estimation

2. Go to File > Save As > Download to download a copy to your computer.  
3. Open the Word file that has been saved to your computer.
4. If using Microsoft Word or a similar program, enable “Track Changes” before editing.
5. When you are ready to submit your comments, please email the document(s) and any other comments to Jennifer Breaux at jbreaux@cim.org.