Glossary of terms relating to building stones of Edinburgh
From: Appendix 1 Glossary. McMillan, A.A., Gillanders, R.J. and Fairhurst, J.A. 1999 Building stones of Edinburgh. 2nd edition. Edinburgh: Edinburgh Geological Society.
Agglomerate: rock produced by explosive volcanic activity - coarse angular blocks in a fine-grained matrix.
Andesite: fine-grained, volcanic rock consisting of feldspar and iron-magnesian silicate minerals.
Anhydrite: mineral composed of calcium sulphate (see also gypsum).
Anticline: strata folded in the form of an arch.
Architrave: the lowest horizontal member lying above a column in a colonnaded building.
Ashlar: hewn blocks of masonry finely dressed to size and laid in courses.
Baillie: magistrate in Scottish local government
Barrack: accommodation for itinerant workers, sometimes temporary.
Basalt: black, fine-grained, basic igneous rock, commonly forming lava flows and consisting of iron oxide and silicate minerals including feldspar and pyroxene.
Bedding: natural layers formed during deposition of sediments.
Blaes: old mining term for mudstone or shale, not containing much bituminous material.
Boaster: broad-faced chisel used for dressing stones.
Braided: interwoven stream or river channels, constantly shifting through islands composed of sands, silts and clays.
Broached: Scottish term for work on stone face with pointed tool to produce vertical or horizontal furrows.
Calcite: calcium carbonate, a common constituent of limestone.
Camstone: fine-grained, calcareous stone used for whitening doorsteps.
Cementstone: fine-grained, muddy limestone.
Cladding: thin slabs of stone used as external, non-load-bearing covering to building structure.
Column: free-standing vertical member, normally circular in plan, often conforming to the classical orders.
Conglomerate: sedimentary rock consisting of water-worn pebbles bound together in a sandy matrix.
Corbel: stone or series of stones projecting from a wall used for support.
Cornstone: concretionary limestone formed under arid conditions.
Corinthian: the most ornate of the variations on post and lintel structure found in classical architecture.
Course: continuous layer of stones of uniform height.
Coursed rubble: roughly squared stones in courses to correspond with quoin and jamb stones.
Cross-bedding: in sands a series of inclined bedding planes having a relationship to the direction of current flow (also current-bedding).
Cyclothem: repeated unit in cyclic sedimentation.
Desiccation: the process of drying up.
Dimensioned stone: ashlar or stone prepared to specified dimensions.
Dip: inclination of strata to the horizontal.
Dolerite: black, medium-grained basic igneous rock consisting of iron oxide and silicate minerals including feldspar and pyroxene.
Draft: smooth strip worked on stone face to width of draft chisel.
Dressed: applied to stone with any kind of worked finish.
Droved: tooled with a broad chisel.
Dune-bedding: large-scale cross-bedding typical of sands deposited in desert and beach dunes.
Dyke: sheet-like body of igneous rock which cuts across the bedding of the sedimentary rocks (see also sill).
Efflorescence: development of crystallisation of salts on wall surfaces.
Evaporite: deposit of precipitated salt (e.g. anhydrite, gypsum), evaporation having caused the necessary concentration.
Fault: fracture in rock along which there has been an observable amount of displacement.
Feaks (Fakes): old mining term for thinly bedded shaly, micaceous sandstone or sandy shale (see also flagstone). Feldspar: important group of rock-forming silicate minerals including silicates of sodium,
potassium and calcium.
Felsite: fine-grained igneous rock consisting of feldspar and quartz.
Flagstone: fissile, micaceous laminated sandstone, suitable for roofs and pavements.
Freestone: see Liver Rock.
Gabbro: coarse-grained igneous rock consisting of feldspar and magnesium- and iron-rich silicate minerals including pyroxene and sometimes olivine.
Gin: machine used in hoisting often driven by horses.
Graben: block of the earth's crust down-thrown between two faults.
Granite: coarse-grained igneous rock consisting of quartz, feldspar and very commonly mica.
Greywacke: fine- to coarse-grained, hard sandstone consisting of mainly angular quartz and rock fragments (also known as wacke).
Gypsum: soft white mineral composed of hydrated calcium sulphate.
Indenting: Scottish term for cutting out worn or damaged stone and inserting new (indents).
Ionic: simpler variation of the post and lintel structure found in classical architecture (see also Corinthian).
Jamb: stones forming the vertical surfaces at the sides of doors or windows.
Joint: fracture in the rock with no displacement. Joints often occur in two sets, more or less vertical and at right angles to each other.
Jumper: hand tool for sinking holes in stone.
Limonite: hydrated iron oxide and hydroxide.
Lithology: character of rock in terms of composition, structure and grain size.
Liver rock: massive sandstone without discernible bedding which can be worked in all directions (also freestone).
Mash: Scottish term for Mason's steel hammer weighing 1-2kg.
Metamorphic rock: recrystallized rock derived from pre-existing rocks by action of high temperature and/or pressure in the earth's crust.
Mica: flaky complex hydrated silicate mineral.
Newel: upright column around which the steps of a spiral staircase wind.
Ostracod: minute creature which has jointed limbs and lives inside a bivalve shell.
Pilaster: shallow pier or part column projecting from a wall.
Pillar: free-standing vertical block of stone: circular or polygonal in plan.
Pillar and Stall: method of mining which involved leaving pillars of the material being mined to support the roof (also known as stoop and room).
Pitched: surfaces resembling natural rock produced by pitching tool.
Plat: platform, doorstep or landing.
Plug and Feathers: steel wedge (plug) with half-round steel strip (feathers) on either side, used for splitting stone.
Polished: stone surface worked to a very smooth finish by rubbing.
Pyroxene: group of iron and magnesium (ferro-magnesian) silicate minerals.
Quartz: common rock-forming, hard glassy mineral, silica.
Quoin: stone at external angle of wall.
Random rubble: walling of irregular unsquared stones.
Redd: quarry rubbish.
Rubble (ruble): rough uncut stones of irregular shape and size.
Rusticated joints: where margins of stones are sunk below the general face.
Sandstone: sedimentary rock composed of sand grains naturally cemented.
Scaling: stone flaking-off in thin layers.
Scleroscope: small diamond-tipped rebound hammer used for measuring hardness of a material.
Seatearth: rock composed of clay-, silt- or sand-grade material full of fossilised plant roots, representing a former soil.
Sett: stone roughly squared for paving (also calsay stones).
Sill: sheet of igneous rock intruded along the bedding planes of earlier rocks.
Sneck: small stone in squared rubble work to make up bed bonding.
Squared rubble: walling of irregular squared stones laid in courses.
Stratigraphy: study of stratified rocks including their sequence in time and the correlation of sedimentary sequences in different localities.
Stugged: pecked stone faced with a pick or pointed tool.
Syenite: coarse-grained igneous rock consisting mainly of potassium-rich feldspar and hornblende.
Till: stiff to hard clay with stones, deposited by ice (also boulder clay).
Tirr: material removed as overburden.
Tuff: consolidated volcanic ash.