Mayflower Mine, Rossland, Trail Creek Mining Division, British Columbia, Canadai

Regional Level Types
Mayflower Mine	Mine
Rossland	Town
Trail Creek Mining Division	Division
British Columbia	Province
Canada	Country

The former Mayflower mine is located 2 kilometres south of the city centre of Rossland, British Columbia.
The following quote is from B.C. Government site “Minfile”- Minfile No. 082FSW 146, current to 2020:
“The old Mayflower mine workings are hosted by the Lower Jurassic Rossland Group (Elise Formation) augite porphyry, known as the Rossland sill. The porphyry is dark green with phenocrysts of dark augite which are partly altered to hornblende. The rock is commonly brecciated with preferential epidote alteration. The sill is intruded by the Early Jurassic Rossland monzonite which is comprised of a biotite-hornblende-augite monzonite. The sill lies within the zone of thermal metamorphism. Diorite porphyry and lamprophyre dykes crosscut these older rocks striking 015 degrees and dipping 50 to 60 degrees eastward. A sample from a crosscutting lamprophyre dyke on the Mayflower claim gave a potassium-argon date from biotite as 49.4 plus or minus 1.4 million years (Bulletin 74, page 54).
The mine is hosted by the Bluebird (sic)-Mayflower shear zone which strikes 120 to 130 degrees and dips from 50 to 65 degrees to the northeast, and is traceable for 600 metres. The Mayflower zone, located about 200 metres east of the Blue Bird zone (082FSW145) on the same structure, is similar in most respects to the Blue Bird zone but differs in its higher gold to silver ratio. Exploration has been carried out to a depth of 60 metres at which level the mineralization is still present. Limited drilling between the Blue Bird and Mayflower zones, to a depth of 45 metres, has confirmed continuity of the mineralized structure, but grades have been low. At the western extent of the shear zone, near the Hattie Brown shaft (082FSW359), the structure is cut by a 12.2 metre wide monzonite dyke of the Middle Eocene Coryell Intrusions. Surface work and drilling has suggested that the structure continues to the west of the dyke and is mineralized.
The main vein strikes 110 degrees and dips 70 to 80 degrees north. The earliest work was on the South vein; later development work proceeded on the North and Main veins which all strike east-west and dip steeply north. The main portal, at elevation 877 metres intersects 5 main ore shoots of 56 metres in length. Mineralization consists of sulphides replacing wallrock along well-defined fracture and faults and infilling fractures. The ore shoots end abruptly against dykes or cross structures.
The ore is composed of fine-grained, disseminated or rudely banded massive sulphides in a gangue consisting of thoroughly sericitized rock with minor carbonate and quartz. The mineralization is of the South Belt-type which contains pyrite, pyrrhotite, arsenopyrite, sphalerite, galena, and boulangerite (Bulletin 74, pages 39-40). Microscopic examination of the ore suggests that pyrrhotite was the earliest mineral to form, followed by and partly replaced by pyrite and arsenopyrite. Tetrahedrite is generally, closely associated with the galena. Silver assays of ore from the Mayflower property suggests that the tetrahedrite contains perhaps 10 per cent silver (Thorpe, 1967). Ruby silver, probably pyrargyrite is reported to occur in the ore as well as magnetite which is associated with the arsenopyrite.”
Comments by Giles Peatfield regarding some of the minerals reported:
As an overall caveat, it must be stated that many of the referenced reports from which minerals are reported were written before British Columbia “Minfile” was established. Thus it is not always possible to say whether reported occurrences refer to Mayflower (082FSW 146) or Blue Bird (082FSW 145). Because the two mines are apparently on the same general structure and are reported to have similar mineralogy, I have included most of the reported minerals for both properties – see separate Mindat posting for Blue Bird.
Augite: Reported by Fyles (1984) in an altered lamprophyre dyke used for dating.
Biotite: Reported by Fyles (1984) in an altered lamprophyre dyke used for dating.
Boulangerite: Warren and Thompson (1949) reported that this was confirmed at Mayflower by X-ray analysis.
Chlorite: Höy and Dunne (2001) reported chlorite as a minor constituent at Mayflower.
Epidote: Reported by Fyles (1984) in an altered lamprophyre dyke used for dating.
Gold: Reported as occurring in arsenopyrite, especially from and near the Mayflower mine.
Magnetite: Reported as common at Mayflower.
Marcasite: Reported only by Cormick (no date), presumably at Mayflower and Blue Bird.
Meneghinite: Reported only by Gonzalez (1952). Unfortunately, it is not fully clear whether the specimen in which he identified meneghinite, associated with galena and boulangerite, was from the Mayflower or nearby Blue Bird. Gonzalez thanked Dr. R. M. Thompson “. . . for his suggestions leading to the identification of Owyheeite and Meneghinite.” I would regard meneghinite as valid for both localities.
Owyheeite: Reported by Cormick (no date) and by Gonzalez (1952), but again with no precise locations given. I would regard owyheeite as valid for both localities.
Plagioclase: Fyles (1954) reported plagioclase (An48) in the lamprophyre dyke at Mayflower.
Pyrargyrite: Several workers reported pyrargyrite as “possible” in the area; I would regard it as tentative for Mayflower.
Sericite: Reported by Fyles (1984) in an altered lamprophyre dyke used for dating.
Tetrahedrite: This is common at both Mayflower and Blue Bird. Thorpe reported it to have a high silver content.

References

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Link to British Columbia Minfile:	082FSW146

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