Aggregates grading, or gradation

is the distribution of different particles of aggregates by size. Grading
designations are often used to quickly reference the size of aggregates required for a specific application. Both AASHTO and ASTM have standard grading designations for aggregates. For example, #57 is a common aggregates size designation used to signify an aggregates with all material smaller than 11/2-inches but with essentially no fines.

Reference: The Aggregates Handbook

Brownfields Exploration

happens close to an existing mine or deposit. The belief is that nearby locations will have a higher probability of holding similar valuable minerals. The existence of an initial deposit does not guarantee another deposit will be nearby.

Coarse aggregates

is generally considered to be crushed stone or gravel almost all of
which is retained on a No. 4 sieve (4.75mm).

Reference: The Aggregates Handbook

Cut-off grade (product specifications)

The lowest grade, or quality, of mineralised material that qualifies as
economically mineable and available in a given deposit. May be defined
on the basis of economic evaluation, or on physical or chemical attributes
that define an acceptable product specification.

Reference: JORC Code 2012

Critical Raw Materials (CRMs)

defined as raw materials that both have a high economic importance and a large supply risk in the economy of a country or some other region under consideration (Blengini et al. 2020).


Crushed stone

can be composed of limestone, granite, traprock or any other hard,
sound rock that is produced by blasting and then crushing. Crushed stone is produced to meet industry specifications using stationary or portable plants.

Reference: The Aggregates Handbook

Grade or quality, assay, analysis (that is value returned by the analysis)

Any physical or chemical measurement of the characteristics of the material of interest in samples or product. Note that the term quality has special meaning for diamonds and other gemstones. The units of measurement should be stated when figures are reported.

Reference: JORC Code 2012

Fine aggregates

is considered to be any material that passes a 3/8-inch sieve and essentially all of which passes a No. 4 sieve (4.75mm) and is predominantly retained on the No. 200 sieve (75μm).

Reference: The Aggregates Handbook

Greenfields Exploration

happens in undeveloped regions far from other mines. This process is lengthy and investors need to be aware of the high risk associated with prospecting in uncharted territory. There is a chance the company will not find a suitable mineral deposit to provide a return on the initial investment.

Heavy metals

a group of metals and metalloids that occur naturally in rocks but industrial activities as mining increase their environmental release. Some of them are essential for our health and other are toxic and carcinogenic. Recent decades have seen extensive toxicological studies reporting their adverse effect on humans as neurotoxicity, immunodeficiency, osteoporosis, kidneys and other organ failures as well as potential implications in impaired fertility. Heavy metals include lead, iron, mercury, cadmium, arsenic, aluminum, copper, manganese, and others.

Reference: Piotr Rzymski et al., impact of heavy metals on the female reproductive system (2015)

Heavy Rare Earth Elements (HREE)

Europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), yttrium (Y)


the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves prepared by the Joint Ore Reserves Committee of the Australasian Institute of Mining and Metallurgy, Australian Institute of Geoscientists and Minerals Council of Australia, as amended.

Reference: National Instrument 43-101 Standard of disclosure for mineral projects (2011) (NI 43-101)

Light Rare Earth Elements (LREE)

Lanthanum (La), cerium (Ce), praseodymium (Pr), neodymiun (Nd), samarium (Sm)

Mining (quarrying)

All activities related to extraction of metals, minerals and gemstones from the earth whether surface or underground, and by any method (eg quarries, open cast, open cut, solution mining, dredging, etc.)

Reference: JORC Code 2012


the Pan-European Code for Reporting of Exploration Results, Mineral Resources and Reserves prepared by the Pan-European Reserves and Resources Reporting Committee, as amended.

Reference: National Instrument 43-101 Standard of disclosure for mineral projects (2011) (NI 43-101)

Preliminary Economic Assessment (PEA)

a study, other than a pre-feasibility or feasibility study, that includes an economic analysis of the potential viability of mineral resources.

Reference: National Instrument 43-101 Standard of disclosure for mineral projects (2011) (NI 43-101)

Qualified Person (QP) or Competent Person (Australasian) or Qualified Competent Person (Chile)

An individual who
(a) is an engineer or geoscientist with a university degree, or equivalent accreditation, in an area of geoscience, or engineering, relating to mineral exploration or mining;
(b) has at least five years of experience in mineral exploration, mine development or operation, or mineral project assessment, or any combination of these, that is relevant to his or her professional degree or area of practice;
(c) has experience relevant to the subject matter of the mineral project and the technical report;
(d) is in good standing with a professional association; and 
(e) in the case of a professional association in a foreign jurisdiction, has a membership designation that
(i) requires attainment of a position of responsibility in their profession that requires the exercise of independent judgment; and
(ii) requires A. a favourable confidential peer evaluation of the individual’s character, professional judgement, experience, and ethical fitness; or

B. a recommendation for membership by at least two peers, and demonstrated prominence or expertise in the field of mineral exploration or mining.

Reference: National Instrument 43-101 Standard of disclosure for mineral projects (2011) (NI 43-101)

Rare Earth Elements (REE)

The metals included are listed at HREE and LREE, above

Reasonable Prospects for Eventual Economic Extraction (RPEEE)

The phrase ‘reasonable prospects for eventual economic extraction’ implies a judgment by the Qualified Person in respect of the technical and economic factors likely to influence the prospect of economic extraction. The Qualified Person should consider and clearly state the basis for determining that the material has reasonable prospects for eventual economic extraction. Assumptions should include estimates of cutoff grade and geological continuity at the selected cut-off, metallurgical recovery, smelter payments, commodity price or product value, mining and processing method and mining, processing and general and administrative costs. The Qualified Person should state if the assessment is based on any direct evidence and testing.

Reference: CIM Definition Standards (2014)

Recovery (Yield)

The percentage of material of interest that is extracted during mining and/or processing. A measure of mining or processing efficiency.

Reference: JORC Code 2012

Sand and gravel

is any unconsolidated mixture of fine and/or coarse aggregates material found in a natural deposit. Most sand and gravel deposits are formed by deposition in water. Most deposits of sand and gravel are found along stream channels.

Reference: The Aggregates Handbook

Social Licence to operate

community’s perceptions of the acceptability of a company and its local operations.

Reference: Hill, C, Madden, C & Collins, N (2017). A Guide to Gender Impact Assessment for the Extractive Industries, Oxfam, Melbourne.

Technical report

A report prepared and filed in accordance with this Instrument and Form 43-101F1 Technical Report that includes, in summary form, all material scientific and technical information in respect of the subject property as of the effective date of the technical report;

Reference: National Instrument 43-101 Standard of disclosure for mineral projects (2011) (NI 43-101)

Written disclosure

“written disclosure” includes any writing, picture, map, or other printed representation whether produced, stored or
disseminated on paper or electronically, including websites.

Reference: National Instrument 43-101 Standard of disclosure for mineral projects (2011) (NI 43-101)