News

Golden Queen Mining Company’s senior geologist, Sara Holden, will share how the ore control team has increased ore recovery by accounting for blast movement at the Annual conference of the Society for Mining, Metallurgy and Exploration.

Paper Title:

Minimizing Dilution and Ore Loss by Accounting for Blast Movement at Golden Queen Mining Company’s Soledad Mountain Project

Presenters:

Sara Holden, Ore Control Geologist, Golden Queen Mining Company, LLC

Alyssa Kendir, Senior Consultant, Blast Movement Technologies

Abstract:

Controlling ore contacts prior to excavation is essential to ensuring that material types reach the correct downstream locations in order to achieve optimal ore recovery. This practice is especially pertinent to narrow vein or structurally-controlled deposits, where very small discrepancies between assumed and actual locations of the ore contacts can translate to significant ore loss and dilution. However, whether a mine’s priority is to minimize (i) ore loss, (ii) dilution, (iii) contamination, or (iv) adhering to strict blending requirements, blast movement is a problem for every mine, including those targeting massive, disseminated deposits.

An analysis of blast movement was conducted at Golden Queen Mining Company’s Soledad Mountain Project, a narrow vein-hosted gold/silver deposit, to evaluate its effects on ore loss and dilution. Three-dimensional movement at mid-bench locations in numerous blasts were measured. Horizontal movement vectors were calculated, and pre-blast ore polygons were translated to post-blast locations using the measured data.

One example of a monitored blast showed that the entire ore block moved by 4.5 –10.5 ft. Although this movement was modest, such a displacement without tracking would have resulted in an estimated 3% (~4,000 tons) ore loss as a result of ore migrating into a waste block. The overall increase in recovered value from this blast was estimated at US $69,195.

This study illustrates that accounting for blast movement, particularly in vein-hosted deposits, can significantly reduce ore loss and waste processing, resulting in increased ore recovery and improved reconciliation. Tracking blast movement can also assist in understanding and designing blast parameters to optimize ore recovery.

Presentation Mon 25th, Striving for Excellence Case Studies. The SME Annual Conference & Expo runs from Feb 24 – 27, Denver, CO. Find out more