Apatite Ilmenite Zircon

Specimen Summary

Apatite is the name of a group of calcium phosphate minerals: fluorapatite, chlorapatite and hydroxylapatite. All have a similar chemical composition and prismatic hexagonal crystal shape, but varying amounts of fluorine, chlorine and hydroxyl. Hydroxylapatite is one of the main constituents of bone and tooth enamel. Outside of the biological world, fluorapatite is the most common, occurring in igneous, sedimentary and metamorphic rocks. Apatite contains clues like fission tracks that help geologists to understand the Earth's history. Methods like apatite fission track dating tell us about the cooling history of a rock, helping us to understand how fast a mountain belt grew or was eroded, or when a magma body cooled. Apatite is most commonly used to produce fertilizers because it contains phosphate, an important element in plant growth. Sometime rare earth elements, important in modern electronics and magnets, substitute for calcium in apatite. If concentrations of rare earth elements are high enough, apatite can be considered an ore mineral, but only a few apatite rare earth element deposits have been discovered so far.

Orthoclase is a potassium-rich member of the feldspar group. Potassium feldspar, or K-feldpar, is a relatively common mineral, occurring in many types of igneous and sedimentary rocks. It is most commonly pink in colour, but can also be colourless, white or pale green, yellow or grey. It can be easily confused with more calcium- or sodium-rich feldspars. Orthoclase and sodium-rich feldspar (albite) can intergrow to form moonstone, which has a shimmering pale grey-white lustra and is used to make jewellery.

Quartz is the second most abundant mineral on Earth, occurring in many different types of rocks. Although usually clear or milky white in colour, quartz can be found in a variety of colours because of impurities in the crystal structure. Pure quartz is made up of silicon and oxygen only, but atoms of other elements, like iron or titanium, often make their way into the quartz crystal structure. Some varieties of quartz, like purple amethyst, are considered to be semi-precious gemstones and have been used since ancient times to make jewellery and decorative objects.

This sample is from the Blue River area east of Wells Grey Provincial Park in central BC. It contains white orthoclase with well-formed crystals and clear quartz and apatite. Small dark flakes of mica can also be seen.

Specimen Data

 

The information listed below relates to the current holding location or collection that the sample is from, and whether the item is viewable at that location or is part of a private collection. Coordinates are given as guides, and we remind you that collecting specimens from these locations is not allowed. Caution is advised visiting such sites and Below BC assumes no responsibility for any injuries or trespassing charges that may occur as a result of the viewer entering these sites.

Collection Details

Original Collection:

Association for Mineral Exploration (AME)

Sub Collection:

-

Collection ID:

AME-446

Virtual Museum ID:

19-AME446

Accessibility:

Date Added to VM:

2018-02-08

Location Information

Sample Origin:

Blue River, British Columbia

Specific Site:

Verity Claim

UTM Easting:

353331

UTM Northing:

5807654

Datum:

11 (NAD 83)

Coordinate Accuracy:

Approximate

Specimen Details

VM Category:

Mineral

Primary Features:

Apatite Ilmenite Zircon

Primary Mineral Formula:

Ca5(PO4)3(F,Cl,OH) · ZrSiO₄, FeH6O3Ti

Primary Category:

phosphate oxide silicate

Secondary Features:

Advanced Geological Information

 

The following section provides geological data relating to the specimen or the site it was collected from, when available. Information has been obtained from various sources including private and government datasets but may not be up to date. Any geological time periods or ages listed often relate to the primary geology of the area, and may not be the actual date of an event such as mineral formation.

Geological Formation:

Horsethief Creek

Geological Period:

Proterzoic

Stratigraphic Age:

Geological Belt:

Omineca

Geological Terrane:

Kootenay

Minfile ID:

083D 005

Minfile Link:

https://minfile.gov.bc.ca/Summary.aspx?minfilno=083D++005

Site Details:

The property is located in the North Thompson River Valley, approximately 60 kilometres south-southeast of the town of Valemount.

The property is underlain by Proterzoic Horsethief Creek Group metasedimentary rocks and derived gneisses. Medium to coarse crystalline sovite and beforsite carbonatite sills intrude the Horsethief Creek rocks.

In British Columbia, carbonatites are found in a broad zone parallel to and encompassing the Rocky Mountain Trench, extending from the Elkford area northward to Williston Lake. Occurrences within this belt have been subdivided into three sub-belts. Most carbonatite occurrences are found in the central belt, which is predominantly within the Omineca Belt of the Canadian Cordillera and hosts most known stratiform carbonatites in the area between Revelstoke and Valemount. Within this northwest-trending belt, a number of carbonatite layers containing anomalous strontium, niobium, tantalum and rare earth elements occur within the Semipelite-Amphibolite division of the Hadrynian Horsethief Creek Group in the Monashee Mountains near Blue River (Fieldwork 1984). All of these carbonatites have sodic pyroxene and amphibole-rich fenitic margins and are associated with nepheline and sodalite syenites, urtites to meltergites. The time of emplacement of these carbonatites appears to be prior to the deformation and metamorphism associated with the Jura-Cretaceous Columbian orogeny and, in part, related to extension and/or rifting along the western continental margin. A third major extensional event at the end of the Devonian (circa 350 Ma) resulted in the intrusion of carbonatites. Carbonatites and surrounding metasedimentary rocks have been regionally metamorphosed to upper amphibolite grade (kyanite to sillimanite zone; Open File 1987-17; Bulletin 88).

The Verity carbonatite is easily reached by trails and logging roads that cross the North Thompson River and intersect Highway 5 at Lempriere Station, approximately 40 kilometres north of Blue River. This showing has the most varied stratigraphy of all the carbonatites in the area and is similar texturally and compositionally to the Paradise showing (083D 006) and the Lempriere carbonatite showing (083D 028). The Verity also contains the best mineralization of the Blue River carbonatites.

Carbonatite, consisting of banded beforsite and sovite (locally intruding each other), occurs as a 15 to 30-metre thick sill within quartz-hornblende-mica schist and can be traced from the Specimen pit up the hillside for 800 metres to the east-northeast. It likely continues to the Paradise showing, 4.5 kilometres to the east-northeast. A tectonic breccia showing hairline fractures is common in the beforsite. A banded texture caused by layering of the accessory minerals apatite, amphibole, olivine, magnetite, vermiculite, biotite, pyrite, pyrrhotite, pyrochlore, columbite and zircon is common in the sovite unit and less developed in the beforsite unit. Coarse olivine and apatite in sovite units form bands 1 to 5 centimetres thick. Magnetite occurs as discontinuous lenses in sovite layers up to 20 centimetres in diameter. The pyrochlore and columbite crystals occur as octahedrons up to 4 centimetres. The major elements in pyrochlore are sodium, tantalum, niobium and calcium, and locally minor uranium. The major elements in columbite are niobium and iron.

The Blue River property was originally staked in 1950 for vermiculite by O.E. French, a homesteader in the area. Later investigations by French resulted in the discovery of the pyrochlore-bearing carbonatites. In 1952, St. Eugene Mining Corporation Ltd. optioned the property and additional claims were staked. Most of the exploration work, consisting of trenching, sampling and blasting, was confined to the Verity and Mill claims. The property was dropped by St. Eugene and remained idle until June 1976, when J. Kruszewski restaked the area. In June 1978, another trenching and sampling program was conducted under the supervision of E. Myers of Calgary, Alberta, with Kruszewski's assistance. A total of 840 cubic metres of stripping was undertaken and two grab samples were taken. In 1979, Kruszewski was approached by Anschutz (Canada) Mining Ltd. and an option contract was signed in February 1980. In 1981 and 1982, the company conducted geological mapping, drilling and sampling on the Bone Creek, Fir, Mill and Verity carbonatites.

A 1.1-metre sample taken in 1952 assayed 0.6 per cent niobium, 0.095 per cent uranium and 4.85 per cent phosphate (Minister of Mines Annual Report 1952). In 1982, the highest drill intersection was 0.025 per cent uranium over 1.5 metres. The Verity carbonatite has indicated reserves of 2 million tonnes of 0.118 per cent niobium and 0.02 per cent tantalum (Assessment Report 11130). Rare earths occur in the carbonatite as indicated by assays of a sample with the following values: 0.0171 per cent lanthanum, 0.0371 per cent cerium, 0.0147 per cent neodynium, 0.0001 per cent ytterbium and 0.002 per cent scandium. This sample also assayed 0.015 per cent tantalum (Open File 1987-17, page 42). Sovites at the Verity showing also contain greater than 4 per cent phosphate and more apatite than any other carbonatite (Assessment Report 10274). The rare earths are thought to be in flurocarbonate.

The property was acquired by Commerce Resources Corporation in 2000 and was grouped together in 2002 with the company’s other carbonatite projects in the area to form the Blue River property. In 2000, Commerce Resources undertook a geological mapping and limited sampling program. Work continued the following year with prospecting, stream sediment sampling, ground geophysical surveys, soil sampling and diamond drilling. Commerce Resources Corporation drilled 410 metres over five holes in 2001 and, based on previous drilling, reported a new inferred resource of 3.06 million tonnes grading 196 grams per tonne tantalum, 646 grams per tonne niobium and 3.2 per cent phosphate (Press Release - Commerce Resources Corporation, July 25, 2001). Geophysical work in 2001 demonstrated that magnetic properties of the Verity Paradise Carbonatite Complex could be used to trace the subcrop edge and potentially locate new carbonatite occurrences.

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