OR/13/015 Appendix 1 - Field descriptions of Falkirk building stones

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Gillespie, M R, Everett, P A, Albornoz-Parra, L J, and Tracey, E A. 2013. A survey of building stone and roofing slate in Falkirk town centre. Nottingham, UK, British geological Survey. (OR/13/015).

This appendix contains a summary description and associated photographs for each of the twenty building stones recorded in the Falkirk THI area (see section 3). A near-focus photograph (at the scale of a masonry block) is provided with the description for each stone, to illustrate its typical colour and character. For sandstones and limestone, a photograph of the reference building on which the description was based is also provided. For modern buff sandstones, which are commonly present as indents and additions to original masonry, the photograph of the reference building is centred on the indented blocks or additions.

Stone code: SB1
Stone name: Buff sandstone 1
Reference building: 1 Glebe Street/16-18 Newmarket Street
PRIMARY_KE 963254
Colour of exposed surfaces: various shades of buff
Grain-size medium-sand-grade to coarse-sand-grade; granule-grade locally Primary sedimentary structure: blocks are commonly bedded; parallel bedding, cross-bedding,

parallel lamination, laminated foresets and rare wispy lamination are all developed locally; buildings usually contain some uniform blocks, and in some buildings most blocks are uniform

Distinctive features: rare flakes of carbonaceous matter; gritty locally
Composition: impure



Stone code: SB2 Stone name: Buff sandstone 2 Reference building: Vicar Chambers, 27-35 Vicar Street PRIMARY_KE 963213 & 963214 Colour of exposed surfaces: buff, with an orangeish to pinkish tinge locally Grain-size: fine-sand-grade to medium-sand-grade Primary sedimentary structure: most blocks are uniform; rare cross bedding; convoluted structure visible on surfaces of soiled/weathered blocks Distinctive features: none, but this stone is rarely visible at ground level Composition: impure Comments: some blocks are gritty


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Stone code: SB3 Stone name: Buff sandstone 3 Reference building: 1 Princes Street PRIMARY_KE 963222 Colour of exposed surfaces: light buff to very light buff (almost white) Grain-size: fine-sand-grade to medium-sand-grade Primary sedimentary structure: uniform Distinctive features: scattered flakes of carbonaceous matter; faint Liesegang bands; scattered brown mud flakes locally Composition: relatively siliceous Comments: weakly micaceous



Stone code: SB4 Stone name: Buff sandstone 4 Reference building: 25-29 Newmarket Street PRIMARY KE 963267 and 963266 Colour of exposed surfaces: light grey to light greyish buff Grain-size medium-sand-grade and coarse-sand-grade Primary sedimentary structure most blocks are uniform; parallel bedding developed locally; rare cross-bedding; rare lamination Distinctive features: micaceous; scattered flakes of carbonaceous matter are usually present, and curved to sinuous leaf fragments up to 5 cm long may be present; can be gritty locally; brown iron nodules up to 2 cm across are developed locally; Liesegang bands can be developed locally Composition impure



Stone code: SB5 Stone name: Buff sandstone 5 Reference building: 123-127 High Street (WH Smith) PRIMARY_KE 961149 Colour of exposed surfaces: light brownish buff Grain-size: medium-sand-grade to coarse-sand-grade; even grain-size Primary sedimentary structure: essentially uniform; rare, faint hints of bedding Distinctive features: strongly micaceous; rare fragments of carbonaceous matter up to 3 cm long; rare iron nodules up to 1 cm across; speckled character given by scattered, dark brown detrital grains up to 3 mm diameter Composition: impure



Stone code: SB6 Stone name: Buff sandstone 6 Reference building: 1 Mission Lane/9 Dundee Court (middle section of elevation facing Williamson Street) PRIMARY_KE 961110 Colour of exposed surfaces: dull yellow Grain-size: fine-sand-grade to medium-sand-grade; even grain-size Primary sedimentary structure: mainly uniform; parallel bedding developed locally; cross bedding developed rarely Distinctive features: micaceous Composition: impure Comments: stone appears to have a high clay content; stugging conceals the primary sedimentary structure in many blocks; spalling extensively where face-bedded




Stone code: SB7 Stone name: Buff sandstone 7 Reference building: dressings to tenement at 36-44 Melrose Place, Dundee Court PRIMARY_KE 961203 & 961204 Colour of exposed surfaces: dull yellowish buff Grain-size: coarse-sand-grade to very-coarse-sand-grade; locally gritty Primary sedimentary structure: uniform, parallel bedded and cross-bedded Distinctive features: locally micaceous; gritty Composition: siliceous Comments: this stone found only as dressings



The photograph at right is centred on the door of the tenement building in which SB7 forms the dressings (dull yellow blocks)

Stone code: SBM1 Stone name: Modern buff sandstone 1 Reference building: indents to Tattie Kirk, off Cow Wynd PRIMARY_KE 961108 Colour of exposed surfaces: buff Grain-size: fine-sand-grade to medium-sand-grade; even grain-size Primary sedimentary structure: most blocks are uniform; faint bedding visible locally Distinctive features: rare flakes of carbonaceous matter up to 5 cm long Composition: impure Comments: weakly to moderately micaceous


The photograph at bottom shows part of Tattie Kirk, where SBM1 forms indents to the window dressings and replacement quoins.



Stone code: SBM2 Stone name: Modern buff sandstone 2 Reference building: Fa’ Kirk (Old Parish Church); also known as Falkirk Old and St Modans Church, Manse Place; elevation facing Newmarket Street PRIMARY_KE 46333727 Colour of exposed surfaces: dull greyish buff Grain-size: medium-sand-grade Primary sedimentary structure: most blocks are uniform; faint bedding visible locally Distinctive features: weakly gritty Composition: impure



The photograph at right shows where SBM2 has been used to build a modern addition to the Newmarket Street elevation of Fa’ Kirk.

Stone code: SBM3 Stone name: Modern buff sandstone 3 Reference building: 3 Vicar Street PRIMARY_KE 963224 Colour of exposed surfaces: buff Grain-size: medium-sand-grade Primary sedimentary structure: uniform Distinctive features: flakes of carbonaceous matter, iron nodules and a gritty character are generally rare but common locally; Liesegang bands are developed locally; coloured spots up to 10 cm diameter are developed around small iron nodules Composition: impure




Stone code: SBM4 Stone name: Modern buff sandstone 4 Reference building: ground and lower floors of The Steeple, High Street PRIMARY_KE 961318 Colour of exposed surfaces: buff Grain-size: medium-sand-grade; even grain-size Primary sedimentary structure: uniform (weakly aligned flakes of carbonaceous matter reveal the bedding orientation in some blocks) Distinctive features: weakly micaceous; scarce flakes of carbonaceous matter are up to 2-3 cm long; nodules of hard brown iron up to 2 cm across are developed locally, with small iron-stained halos; rare fossil shell fragments are up to 8-9 cm long Composition: impure Comment: in 10 Newmarket Centre, (PRIMARY_KE 963303) this stone is fine-sand-grade



The ground and first floor levels of The Steeple are clad in SBM4.


Stone code: SBM5 Stone name: Modern buff sandstone 5 Reference building: indents to Lloyds TSB, 137-139 High Street PRIMARY_KE 961164 Colour of exposed surfaces: dark buff to buff Grain-size: coarse-sand-grade; even grain-size Primary sedimentary structure: essentially uniform; aligned flakes of carbonaceous matter and mica define the bedding orientation locally Distinctive features: micaceous; scattered flakes up to 1 cm long and circles (leafs) up to 8 cm long of carbonaceous matter are common Composition: impure





The photograph at right shows SBM5 indents to the right of the window.


Stone code: SBM6 Stone name: Modern buff sandstone 6 Reference building: ground floor addition to 138-140 High Street PRIMARY_KE 961316 Colour of exposed surfaces: buff Grain-size: generally medium-sand-grade to coarse-sand-grade; locally granule-grade Primary sedimentary structure: parallel bedding, cross-bedding, lamination and wispy lamination are all developed locally Distinctive features: gritty character and Liesegang bands are developed locally Composition: impure




The photograph at right shows the shop front addition to the Bank of Scotland building, which is made entirely of SBM6.


Stone code: SO1

Stone name: Orange sandstone 1 Reference building: St Andrew's West Church, Upper Newmarket Street PRIMARY_KE 46333726 Colour of exposed surfaces: orange to pink Grain-size: medium-sand-grade Primary sedimentary structure: regular, parallel lamination; rare blocks show cross-bedding Distinctive features: speckled character given by scattered grains of white feldspar; rare granulation seams; grey siliceous laminae Composition: siliceous Comments: very rare, hairline veins of calcite




Stone code: SO2 Stone name: Orange sandstone 2 Reference building: 41-43 Vicar Street PRIMARY_KE 963216 & 963217 Colour of exposed surfaces: orange Grain-size: fine-sand-grade Primary sedimentary structure: parallel bedding, cross-bedding and parallel lamination Distinctive features: scattered shallow pits ~1 cm diameter, sometimes concentrated in bands Composition: siliceous




Stone code: L Stone name: shelly limestone Reference building: 165-169 High Street PRIMARY_KE 961200 Colour of exposed surfaces: pale grey Grain-size: fine-sand-grade to medium-sand-grade Primary sedimentary structure: weak bedding defined locally by aligned shell fragments Distinctive features: abundant shell fragments up to 10 cm long Composition: shelly limestone




Stone code: G1 Stone name: Granite 1 Reference building: plinth of South African War Memorial, Newmarket Street PRIMARY_KE 930773 Colour of exposed surfaces: very pale orangeish grey Grain-size: coarse-crystalline (fine division) Texture: equigranular; weakly foliated Distinctive features: none Composition: muscovite-biotite granite





Stone code: G2 Stone name: Granite 2 Reference building: base course of 137-139 High Street PRIMARY_KE 961164 Colour of exposed surfaces: dark grey Grain-size: coarse crystalline (fine to medium division) Texture: largely equigranular but weakly inequigranular (feldspar-phyric) in places; foliated Distinctive features: micaceous; scattered black patches (mafic enclaves) up to 5 cm across Composition: biotite-rich granodiorite




Stone code: G3 Stone name: Granite 3 Reference building: base course 134-136 High Street PRIMARY_KE 961315 & 961350 Colour of exposed surfaces: greyish pink Grain-size: coarse-crystalline (medium to coarse division) Texture: inequigranular (weakly feldspar-phyric); massive Distinctive features: rare dark patches (mafic enclaves) are up to 3 cm across Composition: biotite granite





Stone code: G4 Stone name: Granite 4 Reference building: columns in main door arch, 12-14 Newmarket Street PRIMARY_KE 963306 Colour of exposed surfaces: brownish pink Grain-size: coarse-crystalline (medium division) Texture: equigranular; massive Distinctive features: none Composition: biotite granite