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Pegmatite Mineralogy: Cross Lake, Manitoba

Last Updated: 17th Apr 2018

By Richard Gunter

Pegmatite Mineralogy: Cross Lake, Manitoba.

Richard Gunter
5493 Cedarcreek Drive
Chilliwack, British Columbia, Canada V2R 5K4
pamrichg@shaw.ca


Abstract:

The Cross Lake Pegmatite Field is a complex system of four pegmatite suites. Two of the suites; the Northern Series and the Southern Series contain rare minerals. The #22 pegmatite in the Northern Series contains three type localities for: bobfergusonite, manitobaite and pieczkaite. The remainder of the pegmatites contains suites of minerals typical of the Beryl-Columbite Pegmatite Type (Northern Series) and the Spodumene-Columbite Pegmatite Type (Southern Series).

The nomenclature of the pegmatites has been a problem in the literature due to vague locality information in published papers. The pegmatite containing the type localities should be referred to as Pegmatite # 22 (Anderson, 1984), not the Gottcha Claims (post 1986) or the Cross Lake Pegmatite (Tait et al., 2011) as it is one of 10 beryl-columbite pegmatites in the Northern Series, numbered by Anderson.

Table of Contents:

Abstract:

Tables, Figures and Images:
Introduction:

Geological Setting:

Pegmatite Locations:

Mineralogy:

Northern Suite:

Southern Suite:

Minerals:

Oxides:

Columbite-Tantalite

Phosphates:

Apatite
Beusite
Bobfergusonite
Manitobaite
Pieczkaite
Triploidite

Silicates:

Beryl
Muscovite
Schorl
Spodumene


Conclusions:

Acknowledgements:

References:


Tables, Figures and Images:


Tables:
Table 1: The Paragenesis of the Northern Series Pegmatites (Anderson (1984)
Table 2: The Paragenesis of the Southern Series Pegmatites (Anderson (1984)

Figures:
Figure 1: Geological Map of the Cross Lake Greenstone belt.
Figure 2: Location Map of the Cross Lake Greenstone Belt in the Regional Geology
Figure 3: Location of Pegmatites, Cross Lake Greenstone Belt from Anderson (1984)
Figure 4: Location of #22 Pegmatite, Cross Lake from Tait, Hawthorne and Cerny (2011)
Figure 5: Columbite-Tantalite Chemistry Cross Lake Pegmatites from Anderson (1984)
Figure 6: Backscatter Image of the Beusite Suite
Figure 7: Fillowite Image from the RRUFF database
Figure 8: Annotated Backscatter Image of the Mn content of an Apatite Mass from Pegmatite # 22

Images:
Image 1: Columbite-Tantalite from Pegmatite #36
Image 2: Columbite-Tantalite from Pegmatite #9
Image 3: Apatite from Pegmatite #36
Image 4: Beusite-Fillowite aggregate from Pegmatite #22
Image 5: Bobfergusonite crystals from Pegmatite #22
Image 6: Euhedral Bobfergusonite crystal from Pegmatite #22
Image 7: Manitobaite crystal from Pegmatite #22
Image 8: Euhedral Triploidite from Pegmatite #22
Image 9: Beryl from Pegmatite #36
Image 10: Beryl from Pegmatite #9
Image 11: Gemmy Beryl and Columbite-Tantalite from Pegmatite #36
Image 12: Beryl Shell surrounding apatite from Pegmatite #36
Image 13: Schorl Inclusion in Muscovite from Pegmatite #22
Image 14: Euhedral Spodumene in Quartz from Pegmatite #9.

Anderson Figures:
Figure 31: Lineated Schorl, Almandine and green Apatite; Pegmatite# 36 in situ.
Figure 70: Unknown Phosphate crystal from Pegmatite #22 in situ
Figure 51: White Beryl from Pegmatite #9 in-situ
Figure 53: “Stuffed” Beryl from Pegmatite #37 in-situ
Figure 50: Euhedral Spodumene crystal from Pegmatite #9 in-situ


Introduction:

A suite of small, tantalum-niobium rich pegmatites occur in the south west corner of Cross Lake, Manitoba, southwest of the community of Cross Lake and north of the north end of Lake Winnipeg. The pegmatites can be divided into four suites, two of which contain Ta/Nb/Be minerals and will be described in detail. The remaining two are K-spar/muscovite pegmatites that do not contain abundant rare minerals.

The mineralized pegmatites are divided into two suites. The Northern Suite is beryl-columbite pegmatites that contain elevated phosphate content. They include pegmatite #22 that is the type locality for bobfergusonite, manitobaite and pieczkaite. Other phosphates in the suite are the beusite paragenesis from the #22 pegmatite (Cerny et al. (1998) and manganese bearing apatite in other Northern Suite pegmatites.

Anderson (1984) identified 10 Northern Suite pegmatites as #s: 22, 23, 24, 36, 37, 38, 39, 40, 41and 42. The Southern Suite are spodumene-bearing dykes, mainly on Spodumene Island. There are no type-locality minerals identified in these pegmatites. Anderson (1984) has identified 12 pegmatites of the Southern Suite on Spodumene Island as #s; 8, 9, 11, 12, 13, 14, 15, 16, 69, 70, 71 and 72.

The pegmatites in the Southern Suite were examined and diamond-drilled by Tanco to investigate their tantalum content. Though the tantalum grades were acceptable the pegmatites were too small to be of commercial importance.

Anderson (1984) is the only study to cover all of the Cross Lake pegmatites. Other studies have concentrated on the # 22 pegmatite and its type-locality phosphate minerals. Characterization articles for bobfergusonite (Ercit et al. (1986), manitobaite (Ercit et al. (2010) and pieczkaite Tait et al. (2015) all pertain to the # 22 pegmatite. The description of the beusite suite in the # 22 pegmatite (Cerny et al. (1998)) compares it to other similar suites in Manitoba and northwestern Ontario. The article by Tait, Hawthorne and Cerny (2011) covers part of the mineralogy of the # 22 pegmatite but not the Beusite suite. They also call the # 22 pegmatite the Cross Lake Pegmatite which is misleading because the # 22 pegmatite is only one of 10 beryl-columbite pegmatites at Cross Lake.


Geological Setting:

Geology Map of the Cross Lake Greenstone Belt

Cross Lake, Manitoba, Canada
Figure 1: Geology Map of Cross Lake; Portion of Manitoba Energy and Mines Geological Compilation Map Cross Lake (1996): 1:250,000 scale.

The 1996 Geological Compilation Map of Cross Lake illustrates the complexity of the metasedimentary package on the islands in Cross Lake that contain the pegmatites. Metamorphic grades within the sedimentary package change rapidly at the multiple fault boundaries that often separate the islands within Cross Lake.


Geology Map of the Regional Greenstone Belts

Cross Lake, Manitoba, Canada
Figure 2: Western margin of the Superior Province in Manitoba and Ontario, subdivided into the volcanoplutonic (black and white), metasedimentary (dashed), plutonic (crosses) and high-grade gneiss (dotted) subprovinces (modified from Cerny 1990). The map shows the location of the graftonite and beusite occurrence at Cross Lake (3, in the Sachigo Subprovince). From Cerny et al. (1998)


The regional geology illustrates the position of the Cross Lake greenstone belt, around # 3, in the context of the other greenstone belts in Manitoba and north western Ontario. The black linear bodies are greenstone belts within the geological provinces. The Cross Lake greenstone belt occurs in the Sachigo Province. The complex metamorphism and block faulting between island groups within Cross Lake may be the source of the chemically distinct pegmatite suites with virtually no overlap in chemical signatures between the Northern Series and the Southern Series.


Pegmatite Locations:

Map of Pegmatites: Cross Lake, Manitoba from Anderson (1984)

Cross Lake, Manitoba, Canada
Figure 3: Location of Pegmatites in the Cross Lake Greenstone Belt from Anderson (1984)
The map from Anderson (1984) illustrates the geographic location of the pegmatites in the Cross lake Greenstone Belt. The village of Cross Lake is off the upper left side of the map. The Northern Series pegmatites are at the top of the map identified by solid circles. The Southern Series are at the bottom of the map identified by filled triangles. The island on which pegmatite #9 is located is called Spodumene Island.


Map of #22 Pegmatite; from Tait, Hawthorne and Cerny (2011)

Pegmatite No. 22, North Group, Cross Lake, Manitoba, Canada
Figure 4: Location and Plan View of # 22 Dyke from Tait, Hawthorne and Cerny (2011)

The map shows the location and a detailed plan of pegmatite #22. The amount of study completed on pegmatite #22 makes it by far the best known of the Northern Series pegmatites. The size and attitude of the #22 pegmatite is typical of the pegmatites on Cross Lake of both the Northern and Southern series. Often these pegmatites have shoreline outcrops with much of the dyke exposed due to the large range of water level in Cross lake in the course of a year.

Mineralogy:

Northern Series:

The Northern Series pegmatites are classic beryl-columbite pegmatites containing: elongate prismatic greenish-yellow beryl; platy columbite Mn; Mn-bearing apatite and other Mn-rich phosphates; colourless muscovite and schorl-elbaite tourmaline. The Northern Series pegmatites have very low iron content and high manganese content. This allows the phosphates to crystallize as some of the most manganese-rich members of their solid-solution series.

There are no cavities within the Northern Series pegmatites. All of the mineral phases are embedded in microcline and quartz. Euhedral gold-coloured beryl is embedded in quartz in pegmatite 36. The other beryl crystals are green coloured.

Paragenetic Chart of Cross Lake Pegmatites

Cross Lake, Manitoba, Canada
Table 1: The paragenesis of the Northern Series pegmatites (Anderson (1984).
The table illustrates the overall complexity of the mineralogy with # 22 pegmatite being the most complex. Bobfergusonite and Manitobaite had not been characterized at this time and the Beusite suite had not been discovered here so all are contained within the “unknown phosphate” basket. The description of Bobfergusonite as the most common of the massive phosphates at # 22 pegmatite makes it likely that most of the unknowns were Bobfergusonite.

The rare phosphates have not been noted in the other beryl-columbite dykes of the Northern series but a deep blue-green manganese-rich apatite is common.

Southern Series:

The Southern Series are lithium-rich with spodumene as a constant mineral within the various pegmatites.
Paragenetic Chart of Cross Lake Pegmatites

Cross Lake, Manitoba, Canada
Table 2: Paragenesis of the Southern Series: (Anderson 1984)
Manganese is less common in the Southern Series and when it does occur it is in the form of spessartine in pegmatites 6 and 20. Phosphate is less common in the Southern Series and occurs as minor blue-green apatite as a widespread phase and triphylite-lithiophilite in pegmatite 4.

There are no cavities in the Southern Series pegmatites but euhedral white beryl and euhedral tan coloured spodumene occur embedded in late-stage quartz.




Minerals:

Oxides:

Columbite-Tantalite (Mn,Fe)(Nb,Ta)2O6:

Black, submetallic, platy crystals of manganese dominant columbite occur in both the Northern Series and Southern Series pegmatites. Anderson (1984) illustrates the chemistry of columbite from most of the pegmatites. They plot mainly in the columbite field with most Mn dominant. He considers the chemistry of columbite within each pegmatite to be homogeneous but adjacent pegmatites can have widely varying columbite chemistry.

In the Northern Series the columbite from pegmatite 36 Image 1 Columbite-Mn and golden Beryl in Albite is 5 to 10 mm wide euhedral crystals with Mn/Mn+Fe of 0.50 and Ta/Ta+Nb of 0.32. This plots well into the columbite field and on the border between the Mn and Fe species. In the Southern Series the columbite from pegmatite 9 Image 2 Columbite-Mn in quartz and colourless alkali-rich Beryl in Quartz

occurs as 1 to 2 mm wide platy crystals with Mn/Mn+Fe of 0.74 and Ta/Ta+Nb of 0.26. This plots well into the columbite field with a preponderance of Mn.

The columbite crystals are not distinguishable by eye and so chemical analyses would be needed to determine the ratios in a columbite sample unless the pegmatite is known.

Ta/Nb Ratios from Cross Lake Pegmatites

Cross Lake, Manitoba, Canada
Figure 5: Columbite-tantalite minerals of the Cross Lake pegmatite field in the FeNb2O6-MnNb2O6-FeTa2O6-MnTa2O6 (mol %) diagram. Note that columbite-tantalite from the Southern series is the most Mn-rich but the most Ta-rich specimens occur in the Northern series. Symbols: Southern Series solid triangles; Northern series solid circles; non-Li-Be-Nb pegmatites open triangles.

Minor amounts of other Ta/Mn oxides have been identified microscopically but none form visible crystals. Ixiolite and wodginite have been found in microscopic amounts and uranoan microlite has been found with Bobfergusonite in pegmatite # 22. Anderson (1984) analyzed the microlite and found it to be Ta dominant but it is metamict so the total was low.

Phosphates:

The Northern Series pegmatites have the highest phosphate concentration of the pegmatites at Cross Lake.

Apatite (Ca5(PO4)3F):

Anderson (1984) noted its presence as small blue-green grains in all of the pegmatites. He considered the apatite in the Northern and Southern series pegmatites to be Mn-rich but he did not analyze them. A mass of blue apatite, probably Mn-rich, occurs as an inclusion in beryl from pegmatite 36 of the Northern Series Image 3 Apatite in Beryl Pegmatite 36. In other portions of the pegmatite the green apatite is massive, as Anderson illustrates in this in-situ photograph of lineated apatite with schorl and almandine.


Beusite (Mn,Fe,Ca,Mg)3(PO4)2-Fillowite (Na2Ca(Mn,Fe)7(PO4)6:

The beusite-fillowite pods were described from the # 22 pegmatite by Cerny et al. (1998). They are associated with, but separate from the bobfergusonite-manitobaite pods. The Beusite –Fillowite pods are coarse-grained intergrown phosphate pods, unlike the single crystals of the Bobfergusonite and Manitobaite pods. The sample Image 4 Beusite-Fillowite aggregate; Pegmatite # 22 was taken adjacent to the Bobfergusonite sample and illustrates the intergrown nature of these pods.


Figure 6: Rounded grains of fillowite (medium grey) with inclusions of triploidite (off-white) and manganoan fluorapatite (black), surrounded and possibly corroded by beusite (pale grey). Cross Lake; BSE image. The scale bar is 200 micron long: from Cerny et al. (1998).

The backscatter image in Figure 3 illustrates the embayed nature of many of the grains within the B-F pods which may imply late-stage reactions between the various phosphate species. The chemistry of the individual phases within the B-F pods was determined by Cerny et al. (1998). They are all highly manganiferous with Mn/Mn+Fe ratios for: beusite of 0.78; triploidite of 0.81 and fillowite of 0.84. All the phases are slightly zincian with beusite 0.06 apfu Zn; triploidite 0.07 apfu Zn and fillowite 0.55 apfu Zn. Fillowite is the only alkali-containing phase in the pods with a Na/Na+Ca ratio of 0.70. Triploidite contains a minor amount of F with 0.09 apfu F and 0.91 apfu OH.

Figure 7: A sample from the RRUFF database. The dark brown portion of the sample has been XRD analyzed as fillowite (it was originally donated as to the RRUFF database as Beusite, the light brown, fine-grained mass on the lower left).

In the RRUFF database sample there are no crystal faces on the fillowite but the Mindat Beusite-Fillowite sample has crystal faces on the fillowite grain. Some of the minerals in the phosphate masses, particularly Triploidite, have a complete set of crystal faces whenever they occur but Beusite is always anhedral.

Bobfergusonite Na2Mn5FeAl(PO4)6:

The first of the rare phosphates identified from the # 22 pegmatite by Ercit et al. (1986). It was identified, briefly described and photographed as an unknown phosphate by Anderson (1984). It occurs as 2 cm nodular masses Image 5 Bobfergusonite nodular masses in Microcline. Bobfergusonite rarely occurs as rhombic crystal sections Image 6 Euhedral crystal section of Bobfergusonite in Microcline.

Bobfergusonite crystals can be dark green or brown colour but all have a strong greenish schiller, first noted by Anderson (1984). The euhedral crystal of bobfergusonite can be distinguished from an aggregate by its consistent schiller. The bobfergusonite crystals always occur as single crystals and aggregates of crystals without reaction rims or intergrowths with other phosphate species. The bobfergusonite crystals grew centimeters from the manitobaite and B-F pods but did not intergrow with them. A photo from Anderson (1984) illustrating the isolated nature of a bobfergusonite crystal in-situ (based on the observation of schiller in the text).

Manitobaite Na16Mn25Al8(PO4)30:

The second of the rare phosphates described from the #22 pegmatite by Ercit et al. (2010). He says: "Manitobaite, ideally Na16 Mn2+25 Al8 (PO4)30, is a new mineral species from Cross Lake, Manitoba, Canada. It occurs as large crystals or cleavage masses intergrown with other phosphate minerals in a phosphate pod in the intermediate and core zones of pegmatite #22 on the southeastern shoreline of a small unnamed island in Cross Lake, Manitoba, about 5 km north–northwest of the Cross Lake settlement, longitude 54° 41′ N, latitude 97° 49′ W. Associated minerals are fluorapatite, chlorapatite, bobfergusonite, eosphorite, dickinsonite, fillowite, triploidite, goyazite, perloffite, beusite, triplite, as well as quartz, K-feldspar, muscovite, schorl, beryl, spessartine, gahnite and (Nb,Ta,Sn) oxides. Manitobaite is opaque in large crystals (up to 4 cm), and transparent to translucent in small (<1 mm) grains. Color varies from green to brown, with a colorless to very pale green or very pale greenish brown streak and a vitreous to resinous luster; manitobaite does not fluoresce under ultraviolet light. The cleavage is perfect on {010}, there is no parting, the tenacity is brittle, and the fracture is hackly."

A non-schiller pod of Manitobaite is seen in this sample
Image 7: Manitobaite in Microcline and Muscovite.

There was a non-schiller green-brown phosphate phase associated with bobfergusonite recognized during the characterization in 1986 but it took many years to quantify the Manitobaite and determine its complex structure. Anderson mentions only the phosphate with a recognized schiller so he saw manitobaite but did not mention it.

Manitobaite forms single crystal nodular masses in a similar fashion to bobfergusonite. The two minerals form in the same zone of pegmatite #22, often in adjacent masses. The widespread suite of phosphate mentioned in the Manitobaite abstract are part of the overall phosphate suite in the # 22 pegmatite and normally do not occur directly with manitobaite.

Pieczkaite (Mn5(PO4)3Cl):

Tait, Hawthorne and Ball (2015) characterized Pieczkaite in 2015. Previously there had been studies on the high Mn apatite from the #22 pegmatite (Tait et al. (2014) and Tait Hawthorne and Cerny (2011)).

Tait et al.(2015) say: Pieczkaite, ideally Mn5(PO4)3Cl, is a new apatite-supergroup mineral from Cross Lake, Manitoba, Canada. It occurs as small patches and narrow veins in large crystals of apatite and (Mn,Cl)-bearing apatite in phosphate pods in the quartz core of a granitic pegmatite. Veins of Mn-bearing apatite narrow to ~25 μm where the Mn content becomes high enough to constitute pieczkaite. It is gray with a grayish-white streak, does not fluoresce under ultraviolet light, and has no observable cleavage or parting.

The variation of Mn content in a mass of apatite in the # 22 pegmatite is illustrated from Figure 4. As can be seen from the chemistry of the apatite phases the higher the Mn content the higher the Cl content until the apatite becomes Mn and Cl dominant.

Figure 8: BSE image of apatite in the core zone of pegmatite #22, sample CL53A. Note only selected wt% values are listed. From Tait Hawthorne and Cerny (2011).

The grains of pieczkaite also occur in manitobaite. They are too small to photograph but are common enough to be present in most samples of high Mn apatite and manitobaite from the # 22 pegmatite.


Triploidite (Mn2(PO4)(OH):

One of the few phosphate phases in the Beusite suite that occurs in euhedral crystals is the monoclinic prismatic mineral triploidite (Cerny et al (1998). It occurs in deep brown euhedral crystals to 1 mm within the Mindat beusite-fillowite sample. It also occurs in muscovite immediately adjacent to the beusite and manitobaite samples.

The sample Image 8: Triploidite brown monoclinic crystals in Muscovite.

The triploidite in muscovite has not been XRD identified but it is identical to the triploidite prisms in the beusite-fillowite sample that was collected immediately adjacent to it.

Silicates:

Beryl (Be3Al2Si6O18):

There are two distinct types of beryl in the Cross Lake pegmatites. The Northern Series has gold to green coloured, prismatic beryl with a small amount of iron but no alkalis. A sample of this beryl is: Image 9: Euhedral gold Beryl from Pegmatite #36.

The Southern Series has tabular, colourless high alkali beryl that looks very different than the Northern Series beryl. A sample is: Image 10: Euhedral white Beryl from Pegmatite 9. Anderson (1984) has a similar sample from Pegmatite #9 in-situ.

Anderson (1984) has a suite of chemical analyses of the two types of beryl. The white, tabular Southern Series beryl is similar in chemistry to the white beryl crystals at the Tanco Mine, with Cs content to 22,590 ppm. The small amount of iron in the Northern Series beryl, up to 0.99% Fe2O3, colours them yellow to yellow green.

Even though both types of beryl are embedded in quartz there are gemmy areas within both types of crystals. The small prismatic beryl on the columbite sample is gemmy and double terminated. Image 11: Gemmy Beryl and Columbite Pegmatite 36.

A small number of the beryl crystals are shells of beryl surrounding aggregates of apatite-microcline-muscovite. An end-on view of the gold-coloured beryl from Pegmatite 36 surrounding an aggregate of apatite is: Image 12: Shell of Beryl surrounding Apatite. Anderson (1984) has a similar photograph of a shell-like beryl, he calls it a “stuffed beryl” in situ from pegmatite #37, adjacent to pegmatite #36.

Muscovite KAl2AlSi3O10(OH)2:

Large, multi-centimeter, colourless crystals of muscovite is a major phase in the Northern Series pegmatites but is not as common in the Southern series. The muscovite crystals from the # 22 pegmatite are noted for the euhedral crystals of triploidite and schorl that they contain. The photos in the triploidite and schorl sections illustrate the embedded crystals.

Schorl NaFe3Al6(BO3)3[Si6O18](OH)4:

Iron-bearing black tourmaline is a common phase in all of the pegmatites with only minor lithium-bearing green tourmaline in the Southern Series pegmatite #6. Anderson (1984) did not analyze the tourmalines in his thesis and called all the black tourmaline schorl and the green tourmaline elbaite.

In pegmatite # 22 the schorl crystals can occur as inclusions in the colourless muscovite. Image 13: Schorl inclusion in Muscovite from the # 22 Pegmatite.
In this sample the double terminated schorl crystal is flattened on the {0001} axis but other schorl crystals were flattened on other axes as well.

Spodumene LiAlSi2O6:

Grey-tan euhedral spodumene is a constant phase in the Southern Series pegmatite. An example from pegmatite #9 Image 14: Euhedral Spodumene in Quartz; Pegmatite #9 illustrates the very good clinopyroxenes outline of the euhedral spodumene crystal. These spodumene crystals are very seldom terminated but Anderson (1984) has a photograph of a euhedral, terminated, spodumene crystal in-situ from pegmatite #9.

Often the euhedral spodumene occurs as multi centimeter long single crystals embedded in colourless quartz. There is often a 1 mm thick rind of fine-grained, colourless, muscovite between the spodumene and quartz.

Conclusions:

The Cross Lake greenstone belt, central Manitoba, Canada contains a series of pegmatites representing the beryl-columbite (Northern Series) and spodumene-columbite (Southern Series) pegmatite types. Most of the pegmatites are typical of their types and contain columbite-Mn and beryl with varying alkali content. The mineralogically anomalous # 22 pegmatite is the type locality for three phosphate species; bobfergusonite, manitobaite and Pieczkaite and is the host for several more. It has been studied extensively for the characterization of the phosphate species but has not been placed in context with the remainder of the pegmatite suites.

The pegmatites have considerable evidence for fractionation of manganese and iron. Bobfergusonite, manitobaite and pieczkaite, only found in pegmatite #22, are very rare minerals. The minerals of the Beusite-Fillowite suite have among the most manganiferous compositions from their respective analyses. There is some evidence for the fractionation within the columbite-tantalite series cumulating in the highest Ta/Ta+Nb ratios associated with Pegmatite # 22.

The nomenclature of the pegmatites has been a problem in the literature due to vague locality information in published papers. The pegmatite containing the type localities should be referred to as Pegmatite # 22 (Anderson, 1984), not the Gottcha Claims (post 1986) or the Cross Lake Pegmatite (Tait et al., 2011) as it is one of 10 beryl-columbite pegmatites in the Northern Series, numbered by Anderson.

Acknowledgements:

I would like to thank the staff of Manitoba Energy and Mines for their assistance in mineral determination for this article. Erin Delventhal is thanked for her help in formatting the photographs.

References:

Anderson A. (1984) The Chemistry, Mineralogy and Petrology of the Cross Lake Pegmatite Field, Central Manitoba. M.Sc. Thesis, University of Manitoba 250 p.
Cerny P., Selway J.B., Ercit C.T., Breaks F.W., Anderson A.J. and Anderson S.D. (1998) Graftonite-Beusite in Granitic Pegmatites of the Superior Province: A study in contrasts: Canadian Mineralogist v. 36, p. 367-376
Ercit T.S., Anderson A.J. Cerny P. and Hawthorne F.C. (1986a) Bobfergusonite, a new phosphate mineral from Cross Lake, Manitoba. Canadian Mineralogist v. 24 pp. 599-604
Ercit T.S., Tait K.T., Cooper M.A., Abdu Y., Ball N.A., Anderson A.J. Cerny P. and Hawthorne F.C. (2010) Manitobaite, Na16 Mn25Al8(PO4)30, A New Phosphate Mineral Species from Cross Lake, Manitoba, Canada. Canadian Mineralogist, v. 48, pp. 1455-1463
Manitoba Energy and Mines (1996): Bedrock Geology Compilation Map Series, Cross Lake, NTS 63I; 1:250,000
Tait K.T., Hawthorne F.C. and Cerny P. (2011) Minerals from the Cross Lake Pegmatite, Manitoba, Canada; Asociacion Geologica Argentina, Series D, publication Especial n. 14 pp. 213-215
Tait K.T., Hawthorne F.C. Ball N. and Abdu Y.A. (2014) Mn-rich apatite from Cross Lake, Manitoba, Canada; Goldschmidt 2014 Abstract p. 2441
Tait K.T., Ball, N.M. and Hawthorne F.C. (2015) Pieczkaite, ideally Mn5(PO4)3Cl, a new apatite-supergroup mineral from Cross Lake, Manitoba, Canada: Description and crystal structure. American Mineralogist, v. 100, pp. 1047-1052






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