Quartz Crystals (double terminated)

Virtual Museum ID: 19-DE12

Specimen Summary


Double-terminated quartz crystals have a termination or point at both ends of the crystal

Quartz is the second most abundant mineral on Earth, present in many different types of rocks. Although usually clear or milky white in colour, quartz is found in a variety of colours due to impurities in the crystal structure. Pure quartz consists of silicon and oxygen only, but atoms of other elements often make their way into the quartz crystal structure, colouring the crystals. Some varieties of quartz, like purple amethyst and yellow citrine, are considered to be semi-precious gemstones and have been used since ancient times to make jewellery and decorative objects. Well-formed (euhedral) crystals of quartz have a hexagonal cross section and are highly collectible.

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:

Dan Ethier (DE)

Sub Collection:

-

Collection ID:

DE-12

Virtual Museum ID:

19-DE12

Accessibility:

Date Added to VM:

2019-08-18

Location Information

Sample Origin:

New Hazelton, B.C.

Specific Site:

Jackson flatts, Skeena River

UTM Easting:

546500

UTM Northing:

6298443

Datum:

09 (NAD 83)

Coordinate Accuracy:

Specimen Details

VM Category:

Mineral

Primary Features:

Quartz Crystals (double terminated)

Primary Mineral Formula:

SiO2

Primary Category:

oxide

Secondary Features:

Illminite

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:

Currier Formation (Bowser Lake Group, Muskaboo Creek assemblage)

Geological Period:

145 to 100.5 Ma

Stratigraphic Age:

Lower Cretaceous

Geological Belt:

Intermontane

Geological Terrane:

Overlap Assemblage

Minfile ID:

104A 083

Site Details:

The Mount Jackson occurrence comprises coal showings found on Mount Jackson, Jackson Flats and McEvoy Flats, 1.6 kilometres due south of the junction between Currier Creek and the Skeena River, about 145 kilometres northeast of the community of Stewart.

These showings form part of the southeast Groundhog coalfield, an oblong (roughly 30 by 80 kilometres) area extending from the headwaters of the Klappan and Little Klappan rivers southeast to Groundhog Mountain. Refer to the Discovery deposit (104A 078), located 5 kilometres northwest, for an overview on the exploration history, regional geology and local geology of the southeast Groundhog coalfield.

The coal seams form part of the Lower Cretaceous Currier Formation (Bowser Lake Group, Muskaboo Creek assemblage) comprising carbonaceous shale, siltstone and sandstone. Multiple coal seams have been documented (Coal Assessment Report 98) on the upper north slope of Mount Jackson (8 to 10 seams), in the lower reaches of Trail and Jackson creeks (6 seams each), Little Creek (3 seams), Falconer Creek and Abraham Creek. Seam widths vary from 0.5 to 3.0 metres thick. Approximately 45 samples were collected between 1982 and 1983, the coal quality analyses varied widely (Coal Assessment Reports 107, 108):

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Range for Raw Coal

Fixed carbon 12 - 89

Ash Content 7 - 84

Volatile matter 4 - 23

Calorific value 800 - 7720

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All values are in per cent except for the calorific value which is in calories per gram. Coal rank varies from anthracite to meta-anthracite.

A single diamond-drill hole in the McEvoy Flats near Abraham Creek intersected 10 coal seams for an aggregate thickness of 6.25 metres (Coal Assessment Report 98). Coal quality testing of the two thickest seams (each exceeding 1.5 metres) gave the following values:

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Upper Seam Lower Seam

Float yield 55.7 69.7

Fixed carbon 70.8 80.6

Ash content 19.8 12.5

Volatile Matter 9.5 6.9

Sulphur content 0.7 0.9

Calorific value 6526 7193

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The float yield is based on a specific gravity separation of 1.75 grams per cubic centimetre.

In 1970, a joint venture between National Coal Corporation Ltd., Placer Development Ltd., and Quintana Minerals Corporation conducted geological mapping and drilling of six boreholes totalling 1029 metres.

Suncor was active in the Mount Jackson area in the early 1980s, opening 50 trenches. In 1988, Gulf Canada conducted trenching, measuring of sections, mapping and sampling at Mount Jackson.

The nomenclature of the coal-bearing rock units in the Mount Klappan area has a complex history. It has been variously referred to as the Currier Formation (Bustin and Moffat, Canadian Society of Petroleum Geologists Bulletin 1983; Macleod and Hills, Canadian Journal of Earth Sciences 1990, and most industry Coal Assessment Reports), the Groundhog-Gunanoot facies (Eisbacher, Geological Survey of Canada Paper 73-33), the Gunanoot assemblage (Richards and Gilchrist, Geological Survey of CanadaPaper 79-1B), and the Groundhog-Gunanoot assemblage (Evenchick and Thorkelson, Geological Survey of Canada Bulletin 577, (2005)). Evenchick and Thorkelson (Geological Survey of Canada Bulletin 577) provide a history of stratigraphic nomenclature in the coalfield, and a discussion of the debate over the age of the coal-bearing unit, which they refer to as the Groundhog-Gunanoot assemblage. The age is not well-constrained, and may vary by area; however, it is mainly between latest Jurassic and late Early Cretaceous.

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