Mariana Minerals is a software-first, vertically integrated minerals company on a mission to supply the critical minerals powering modern energy, AI, and defense technologies. We’re reimagining the minerals supply chain by combining deep industry expertise with advanced software, automation, and data-driven decision-making.
Role Overview
Mariana Minerals is seeking an experienced and detail-oriented Sr. Estimator to lead cost estimation efforts for mining and mineral processing projects. This role is responsible for developing accurate, competitive, and timely cost estimates that support strategic decision-making and project success.
What You’ll Do
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Lead the preparation of detailed cost estimates for mining, processing, and infrastructure projects
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Analyze drawings, specifications, proposals, and other documentation to prepare time, cost, materials, and labor estimate
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Utilize RSMeans data and tools to develop accurate and benchmarked cost estimates
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Collaborate with engineering, procurement, and project management teams to ensure accurate and comprehensive estimate
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Develop and maintain cost databases, benchmarks, and estimating tools
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Identify project risks and opportunities, providing mitigation strategies
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Review and validate subcontractor and supplier quotes
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Participate in bid reviews, value engineering, and project planning sessions
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Provide ongoing cost analysis and support throughout the project lifecycle
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Mentor junior estimators and contribute to continuous improvement initiatives
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Support the PCM and Software Engineering teams in developing operating systems and tools to automate estimating processes
What You’ll Bring
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7+ years of experience in estimating within mining, heavy industrial, or construction environments
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Strong knowledge of mining operations, materials, and equipment
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Proficiency in RSMeans
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Advanced skills in Excel and data analysis
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Ability to interpret technical drawings and specifications
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Strong analytical, organizational, and communication skills
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Availability to travel 20% of the time to site or Mariana Minerals offices
Preferred
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Experience with EPC/EPCM project delivery models
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Familiarity with mining projects
Our culture is built on three principles:
Extreme Ownership – We take full responsibility for outcomes, relentlessly driving toward solutions.
Engineer Out Requirements, then Automate – We simplify, optimize, and then automate for scale.
Share Your Legos – We collaborate openly, share knowledge, and empower each other to build bigger, better solutions.
Join us as we build the future of responsible mineral sourcing and supply.