Technical terms
Exploration Permit
A title issued under Brazil's mineral exploration authorization regime that allows its holder to carry out work aimed at defining a deposit, evaluating it, and determining viability within the limits and conditions set by law and ANM.
Sampling
Collection of a representative portion of soil, sediment, rock, core, or other material for analysis. Design, location, collection method, and quality control directly affect the reliability of later interpretations.
Anomaly
A value, pattern, or response that differs from a background or reference condition. A geochemical, geophysical, or spectral anomaly may justify further investigation but does not, by itself, represent a mineral discovery.
ANM
Brazil's National Mining Agency, the federal authority responsible for managing mineral resources and regulating and supervising mineral development activities in Brazil.
Ion-Adsorption Clays
An occurrence in which rare-earth elements are adsorbed on clay-mineral surfaces, generally associated with intense weathering of certain rocks. These deposits are relevant to some elements and form an important exploration-target class.
Assay
Laboratory determination of the concentration of one or more elements in a sample. Results may be expressed as a percentage, ppm, ppb, or other units depending on the element and analytical method.
Mineral Processing
Physical or physicochemical operations used to separate and concentrate minerals of interest in an ore before subsequent processing stages.
Carbonatite
An igneous rock composed predominantly of carbonate minerals. Certain carbonatite complexes are economically important because of their association with rare earths, niobium, phosphate, and other elements.
Alkaline Complex
A group of igneous rocks characterized by particular chemical enrichments in alkalis. Some alkaline and alkaline-carbonatite complexes are relevant settings for rare-earth mineralization.
Cut-off Grade
A grade used to separate material under technical and economic criteria defined for a study. It is not a geological constant and may change with prices, costs, recovery, technology, and other economic assumptions.
Mineral Deposit
A natural concentration of mineral substances generated by geological processes. Its existence does not automatically mean that an economically recoverable mineral resource or reserve exists.
Mineral Right
A legal position under the regimes for exploration or development of mineral resources belonging to the Union and administered by ANM. Mineral rights and surface ownership are legally distinct concepts.
Rare Earth Elements - REE
A group of 17 elements comprising the 15 lanthanides plus scandium and yttrium.
Exploration Target
A mineral-reporting term for a statement or conceptual estimate of potential where exploration is still insufficient to estimate a Mineral Resource. Potential quantity and grade, when disclosed, should be shown as ranges with their assumptions. It should not be confused with a GEOAI internal Target.
Modifying Factors
Factors considered when converting Mineral Resources into Mineral Reserves, including mining, processing, metallurgy, infrastructure, economics, markets, law, environment, and social and governmental matters.
Favorability
A comparative reading of evidence used to prioritize areas for further investigation. Favorability is not a resource, reserve, or proof of mineralization.
Geochemistry
The study of the distribution, concentration, and behavior of chemical elements in geological materials. Soil, sediment, rock, and other media may reveal patterns and anomalies relevant to exploration.
Gravity Surveying
A geophysical method that measures small variations in Earth's gravitational field. They may reflect density differences among geological materials and support subsurface structural interpretation.
HREE - Heavy Rare Earth Elements
An abbreviation for heavy rare earth elements. The boundary between LREE and HREE varies by convention. For institutional consistency, BTR uses Tb-Lu for heavy lanthanides and treats Y and Sc separately within the rare-earth group.
Leaching
A process in which components in a solid material are transferred to a solution through chemical action. Different routes may be used according to mineralogy and ore characteristics.
LREE - Light Rare Earth Elements
An abbreviation for light rare earth elements. For institutional consistency, BTR places the lanthanides La-Gd in this category while recognizing other technical conventions.
Magnetometry
A geophysical method that measures variations in Earth's magnetic field caused by differences in the magnetic properties of rocks. It is used to interpret subsurface structures, contacts, and bodies.
Permanent Magnet / NdFeB
A magnet that maintains a magnetic field without continuous electrical power. Neodymium-iron-boron magnets are among the highest-performing permanent magnets and mainly use neodymium and praseodymium, with dysprosium and terbium in some applications.
Mineralization
The presence or concentration of minerals or elements of interest in a rock or area. Identifying mineralization does not automatically define a Mineral Resource.
NdPr
An abbreviation for neodymium + praseodymium, often marketed or discussed together because of their importance in the NdFeB permanent-magnet chain.
Mineral Occurrence
A record of the known presence of a mineral substance in an area. It may range from a point indication to better-characterized mineralization and does not, by itself, imply a resource, reserve, or economic viability.
PPM - Parts per Million
A concentration unit. In solids, 1 ppm is approximately 1 mg/kg by mass. It is widely used for elements present at relatively low levels.
QA/QC - Quality Assurance / Quality Control
Procedures used to assess reliability, precision, accuracy, and possible contamination or errors in sampling and analysis. They may include certified reference materials, blanks, duplicates, and independent checks.
Radiometry
A geophysical method that measures natural gamma radiation associated mainly with certain radioactive elements in rocks. It can support lithological mapping and identification of exploration patterns.
Traceability
The ability to identify the origin, transformations, use limits, and revisions of information, evidence, or a decision throughout the process.
REO - Rare Earth Oxides
Rare-earth oxides, a form widely used to report production, resources, reserves, and commercial products in the rare-earth value chain.
Mineral Resource
A concentration or occurrence of solid material of economic interest whose form, grade or quality, and quantity offer reasonable prospects for eventual economic extraction. Location, quantity, grade, continuity, and other geological characteristics are known, estimated, or interpreted from specific evidence and geological knowledge.
Inferred Mineral Resource
The part of a Mineral Resource estimated from limited geological evidence and sampling. It has the lowest confidence among Mineral Resource categories and cannot be converted directly into a Mineral Reserve.
Indicated Mineral Resource
The part of a Mineral Resource estimated with enough confidence to apply Modifying Factors and support planning and viability evaluations. Its confidence is above Inferred and below Measured.
Measured Mineral Resource
The highest-confidence Mineral Resource category. Geological evidence, sampling, and tests support greater confidence in geological and grade or quality continuity for detailed studies.
Mineral Reserve
The economically mineable part of a Measured and/or Indicated Mineral Resource, defined after appropriate studies and application of Modifying Factors. A Mineral Resource does not automatically imply a Mineral Reserve.
Probable Mineral Reserve
The economically mineable part of an Indicated Mineral Resource and, in some circumstances, a Measured Resource. Confidence is lower than for a Proved Reserve but may support a development decision when appropriately supported.
Proved Mineral Reserve
The economically mineable part of a Measured Mineral Resource. It is the highest-confidence Mineral Reserve category, including high confidence in the application of Modifying Factors.
Exploration Result
Data produced by mineral exploration programs that may be relevant to assessing an area but do not necessarily form part of a Mineral Resource or Reserve statement. They may include sampling, drilling, laboratory analysis, and geophysical surveys.
Remote Sensing
Acquisition and interpretation of information about Earth's surface without direct physical contact, usually through satellite or airborne sensors. It may use different spectral bands, radar, and other sensors for territorial and geological mapping.
GIS - Geographic Information System
A computing environment for storing, integrating, analyzing, and visualizing data associated with geographic positions. It relates different information layers within the same spatial reference.
Target - BTR / GEOAI
An area identified by GEOAI with sufficient signals and characteristics to justify further analysis. It is a qualified investigation hypothesis, not a resource, reserve, or mineral-discovery statement.
Grade
The concentration of an element, mineral, or substance in a material, expressed as a percentage, ppm, g/t, or other units. A high grade alone does not determine economic viability.
TREO - Total Rare Earth Oxides
The sum of rare-earth oxides reported in a sample, concentrate, resource, or product. It is an aggregate measure and does not show the distribution of each element; projects with similar TREO may have very different compositions and values.
TREE - Total Rare Earth Elements
The sum of the concentrations of rare-earth elements. It differs from TREO, which expresses those elements converted to oxide forms.
Mineral-classification note
Exploration Results, Mineral Resources, and Mineral Reserves represent progressive levels of knowledge and confidence and should not be used interchangeably. When a term has a formal resource-and-reserve reporting definition, this reference follows principles used by CBRR/CRIRSCO.