RITAG HE E CP ONSERVATION RACTICE NOTES TECHNICAL NOTE 3.6 STONE MASONRY IN SOUTH AUSTRALIA i DEPARTMENT OF ENVIRONMENT AND NATURAL RESOUCES Published by DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES October 1993 ©October Department 1993 of Environment and Natural Resources and David Young © Department of Environment and NovemberNatural Resources; 2007 and David Young Published online without revision DepartmentSeptember 2008 for Environment and Heritage Published online without revision ISSNDepartment 1035-5138 for Environment and Heritage Prepared by State Heritage Branch DesignISSN 1035-5138 by Technical Services Branch TPreparedext and byphotographs State Heritage by BranchDavid Young Design by Technical Services Branch TextDEH andInformation photographs Line by(08) David 8204 Young 1910 Website: www.environment.sa.gov.au DEHEmail: Information [email protected] Line (08) 8204 1910 u Website www.environment.sa.gov.au Email [email protected] Disclaimer WhileCover reasonablephoto: Carved efforts panel have in been Sydney made sandstone. to ensure the contents of this publication are factually correct, Former Marine and Harbours Building, 1884, the Department for Environment and Heritage makes no representations and accepts no responsibility for Victoria Square. the accuracy or completeness of the contents, and shall not be liable for any loss or damage that may be occasioned directly or indirectly through the use of or reliance on the contents of this publication. Printed on recycled paper Cover photo: Carved penal in Sydney Sandstone. Former Marine and Harbours Building, 1884, Victoria Square. ii CONTENTS page INTRODUCTION 1 - 2 IGEOLOGY OF BUILDING STONE 2 - 3 Igneous Rocks Sedimentary Rocks Metamorphic Rocks II CLASSIFICATION OF SA BUILDING STONE 3 - 5 Granite Marble Slate and Flagstone Bluestone Sandstone Limestone Note: Freestone III HISTORY OF STONE USE IN ADELAIDE 6 - 8 1836-1855 The limestone and bluestone period 1855-1885 The sandstone and bluestone period 1885-1945 Limestone, bluestone, sandstone, granite & marble 1945-1990 Modern construction: sawn granite, marble & sandstone IV THE SLATE AND FLAGSTONE INDUSTRIES 8 VREGIONAL VARIETY AND DIVERSITY 8 - 9 Regional variety The South-East The Mount Lofty Ranges Diversity The Barossa Valley Auburn and Gawler Mining towns VI IMPORTED STONE AND THE BALLAST MYTH 9 - 10 VIIPROPERTIES AND USE OF STONE 10 - 18 Stone selection and physical properties Porosity and permeability Bedding Case hardening Stone finishes Types of masonry Mortar joints Weathering and the colour of masonry VIII SYNTHETIC STONE 18 IX HISTORICALLY IMPORTANT BUILDING 19 STONES OF S A FURTHER READING 2 0 iii INTRODUCTION Stone has long been used as a building The high summer fire risks associated material in South Australia, both of with timber walling and the hazards of necessity and as a luxury. Stone was termites meant that by 1860, the vast one of the most readily available building majority of all Adelaide city buildings materials for the settlers of the new colony. were constructed of stone or brick. Local Rough nodular limestone underlay more stone was often the only available walling than half of William Light’s surveyed material in rural areas in the mid- town plan for Adelaide and many early nineteenth century when transport of buildings were constructed of stone heavy items was difficult and expensive. quarried on site. Even the parklands were quarried and the banks of the River Stone gradually became a luxury as Torrens became a series of brick clay and well as a useful building material. Many river gravel pits and shallow limestone city buildings and suburban houses of quarries. the late-nineteenth and early twentieth centuries have front walls of carefully Stone had considerable thermal shaped and carved sandstone but side advantages in the hot climate and it was and rear walls of unshaped rubble of cheaper than brick in the earliest years. limestone, bluestone or sandstone. Tapley Hill Bluestone (note the very square blocks) with brick quoins and dressings. Former Adelaide Workmen’s Homes, 1899 Rock - faced Mount Lofty Sandstone with painted brick quoins 1 Even where the same type of stone was Australian buildings and the history of used on front and side walls (bluestone their use. Also included are some aspects or sandstone) larger, squarer blocks were of the properties and use of stone which reserved for the more public face of the are important to understanding how building. masonry buildings should be conserved. Other Notes in this series deal with bricks, In early buildings of irregular rubble mortars, general maintenance, cleaning limestone and bluestone, brickwork masonry, rising damp and salt attack, was used to form true square corners and the conservation of masonry. or quoins. This necessity later became a characteristic South Australian I GEOLOGY OF BUILDING STONES convention, for in squared sandstone work the use of an additional material for Geologists divide all rocks into three major the corners was unnecessary. However, groups based on their origin: igneous; brick quoins did allow a neat turning of sedimentary; and metamorphic. ‘Stone’ the corner into side and rear walls that usually refers to rock that is quarried were also of brick. Stone had become a and utilised for some purpose, such as luxury reserved for the front walls. building. Today, stone is mostly a luxury, though Igneous rocks the remarkable lightweight limestone from Mount Gambier (which has been Igneous rocks are formed by solidification worked since 1842) still finds economic (crystallization) of hot molten material use as sawn building blocks. Multi-storey known as magma which rises from deep buildings are no longer constructed with in the earth’s crust. When magmas load-bearing masonry walls but with solidify after reaching the earth’s surface, steel and concrete frames supporting volcanic rocks such as pumice and lava a thin skin or cladding. The cladding are formed. Basalt is a volcanic igneous may be panels of glass, concrete, metal, rock often used in building particularly in compressed fibre composites or, in Victoria. Magmas solidifying beneath the more expensive buildings, stones such earth’s surface produce plutonic rocks as granite and marble. Arguably, the such as granite, syenite and gabbro. longevity of a carefully-chosen and well- These are generally coarser in grainsize detailed granite cladding justifies the than volcanic rocks, the coarser grainsize additional capital expenditure. indicating slower cooling. Many varieties of plutonic rocks have been used in South Australia is a major producer of building. building stone and much (particularly granite) is exported to other states and Sedimentary rocks overseas. A list, ‘Operating Building Stone Quarries in South Australia’, which Sedimentary rocks are formed by the includes details of location, operator accumulation of sediment in water and stone type for all building stones in (aqueous deposits) or from air (aeolian current production is available from the deposits). The sediment may consist of Department of Mines and Energy. That rock fragments or particles of various department also has information on the sizes: sandstone being comprised of sand- physical properties of many of the stones size grains; siltstone of silt-size grains; in current production. A list of some of the and shale of compacted clay particles. important building stones to have been Alternatively the sediment may consist worked in the last 150 years is included of the remains of animals or plants (e.g. as part IX of this Note. limestone and coal) or result from chemical precipitation or evaporation (producing This Technical Note is an introduction to materials such as salt and gypsum). the types of stone found in South Mixtures of these materials are common: 2 e.g. clayey-limestones and calcareous- Granite from Black Hill near Mannum, (i.e. lime-bearing) sandstones. Tuff is which in geological parlance is a norite, wind-blown volcanic ash deposited on is known commercially as Imperial land or in water. Some special cases of Black Granite. Granites are generally sediments include those developed within composed of three main minerals: grey the soil profile as a result of chemical quartz, coloured feldspar and lesser action: these include laterite and the amounts of black mica or pyroxene. variety of limestone known as calcrete. The feldspar, which may be white, red, Most of these sedimentary rocks have pink, green, blue or black, is principally been used in building. responsible for the overall colour of the stone. Granites have a terrazzo look, or Metamorphic rocks perhaps more correctly, terrazzo has a granite look. Metamorphic rocks are formed in the solid state from sedimentary or igneous rocks in response to pronounced changes of temperature and pressure within the earth’s crust. Metamorphic rocks include marble (metamorphosed limestone), slate (metamorphosed shale and siltstone), gneiss and schist. These have all been used for building. II CLASSIFICATION OF SOUTH AUSTRALIAN BUILDING STONES The term ‘building stone’ used in this note includes all natural stones used as building, monumental and ornamental materials. A less commonly used term is ‘dimension stone’. This refers to natural building stone that is trimmed or cut to specified shapes or sizes. It should be distinguished from ‘diminuted stone’: stone that is crushed and used as an aggregate, industrial mineral or chemical raw material. Much confusion results from geologists