"Easy pickings" of zeolite minerals from the volcanic hills around Glasgow supplied fine specimens in the 19th century and the area includes the type localities for thomsonite, heulandite and edingtonite.

The non-zeolite and much rarer species, greenockite (cadmium sulphide) was first discovered in the area
during this period also - and as crystals!

The early classic localities are now unfortunately pretty much history: the locations now virtually or completely inaccessible, due to urbanization encroaching upon them,
as is the case with localities such as Bishopton, Erskine, Bowling and Old Kilpatrick.

They remain important as the source of material for study by mineralogists and chemists, such as Jameson and Thomson (jamesonite & thomsonite) and helped, in this way,
advance mineralogy.

CHABAZITE with Calcite.
Old Kilpatrick, Dumbarton.
(c85x55 mms. crystals to 6 mms).

Clyde Plateau Lavas & their Minerals

Composed predominantly of basalt, several other volcanic rocks including trachyte and rhyolite are not uncommon.

The basalt tends to be typically porphyritic. Slaggy, amygdaloidal flows - where mineralization is generally found - are not uncommon. As a result, the lavas may yet contain more sites of mineralogical interest awaiting discovery.

Clyde Plateau Lavas (in pink).

Port Glasgow and Gourock have produced fine smoky quartz in the past. At Boyleston Quarry, Barrhead, prehnite and zeolites were found as well as native copper,
though this site is now off-limits.

The Touch and Campsie Hills, NE of Glasgow,
also yield zeolite minerals, such as stilbite.

Recent finds of heulandite include localities in the Touch Hills and to the west of Glasgow, as well as at the type locality for the mineral at Old Kilpatrick, near Dumbarton.

HEULANDITE
Lang Craigs, Old Kilpatrick, Dumbarton.
Composite crystal group to 2cms on basalt from the type locality.

HEULANDITE
Craigmuschat Quarry, Gourock, Renfrew.
Cavity infilled with brick red xtls; spec. 37x28mms.

DATOLITE - Kilpatrick Hills, Dumbarton.

A transparent, 2mm. colourless crystal.

PREHNITE - Boyleston Quarry, Barrhead, Renfrew.
Botryoidal aggregates; (spec: 75x60mms).

GREENOCKITE (cadmium sulphide)

Greenockite regularly occurs as yellowish, powdery coatings or as a colouring pigment in other minerals,
such as hemimorphite. (Wanlockhead, Dumfries, Scotland).
However, small, hexagonal pyramidal crystals are very rare.

Crystals are known from Tsumeb (Namibia), Llallagua (Bolivia) and Paterson (New Jersey, USA). Nevertheless, the distinctive crystals from the type locality, Bishopton, Renfrewshire, are the finest for the species, reaching 4-10 mms in length and larger in the best examples.

First discovered when constructing a railway tunnel between Glasgow and Greenock in the 19th century, it was described as a new species by Professor Jameson of Edinburgh University, in 1840, and named after Lord Greenock, the landowner.

Dr. Brown, a Scottish collector of the period, had greenockite crystals in his collection pre-dating that year, but these were assumed to be an unusual form of sphalerite (zinc sulphide). An article by T. Meikle (see references) details the early finds, including Brown's, and accounts why the type locality may not be that listed.

GREENOCKITE - Erskine, Renfrew.
A rough, hexagonal, pyramidal prismatic crystal to 5mms

Several localities in the Glasgow area have yielded,
albeit sparingly, greenockite crystals.
These include Bishopton, Bowling, Erskine and Barrhead.
Loanhead Quarry (Beith, Ayrshire) has, more recently, been added to this list. The mineral is restricted to the Clyde Plateau Lavas of Carboniferous age.

Extensive around Glasgow, these lavas also include the type localities for heulandite and edingtonite. Prehnite and zeolites are typical associates of greenockite,
but the latter remains the most elusive and prized species.
Finds and good examples are very rare.

Other Mineral Occurences

Veins have been worked in the past at Lochwinnoch in Renfrewshire for high grade barite. The Muirshiel Mine was a valuable producer of that mineral in the post-World War II years until extraction ceased in the 1970s.
During its working lifespan, some specimens were saved and, more recently, interesting specimens of strontianite and barite have been recovered. The site, however, is now in a protected park area.

Limestone quarries can be good sites for fossils and, occasionally, for minerals too, and there are a number
of such sites in this region. Mineralisation caused by intrusive Tertiary dykes may also add extra interest.
Loanhead Quarry in northern Ayrshire is a prime example.

Fluorite, a rare species for Scotland, may be found in either of these environments.

BARITE - Muirshiel Mine, Renfrew.
Platy crystal groups of white "cockscomb" variety.
(spec: 90x50 mms).

ALBITE - Reilly Quarry, Houston, Renfrew.
Intergrown, reddish crystals forming a group to c.2mms.

STRONTIANITE - Muirshiel Mine, Renfrew.
Groups of tabular, hexagonal crystals to c 1mm,
stacked to form botryoidal aggregates.

STRONTIANITE - Muirshiel Mine, Renfrew.
Botryoidal aggregate of hexagonal crystals.