STONE AND CERAMICS

1. STONE MATERIALS: a) Natural stone b) Stone binders c) Artificial stone Technology

1. Stone materials Stone is extracted from natural deposits. Stone materials are often used for construction because they are strong, durable and very resistant to weather conditions. Technology

1.1. Extracting and processing stone A) Stone blocks (granite, marble) - Quarrying: we can use controlled explosions or mechanical drilling.A diamond wire saw is used to cut the stone into smaller pieces for transport to a processing plant. https://www.youtube.com/watch?v=KVuCjH8jd bw

Processing: Cutting: Diamond saws are used to cut stone into smaller, thinner sheets. Shaping: Machines called lathes give the stones sheets their final shape. Polishing: machines with abrasive discs are used to smooth the stone.

B) Aggregates (gravel, sand) Aggregates are created in quarries when large blocks of stone are cut. They must be processed: - Cleaning: wood and dirt is removed through washing and drying. - Crushing: gravel is broken into smaller pieces by pressure. - Sorting: the grains are separated by size.

Extracting and processing stone Stone blocks Quarrying Processing Cutting Shaping Polishing Aggregates Cleaning Crushing Sorting

1.2. Natural Stone Limestone Marble Granite Slate Tuff (toba)

A) Limestone: is a porous, off-white sedimentary rock A) Limestone: is a porous, off-white sedimentary rock. Used for sculptures and buildings, as well as for breakwaters in ports.

B) Marble: is a hard, dense metamorphic rock which is formed from limestone. It is resistant to compression and extreme water conditions. It is used to make sculptures, decorations, floors, kitchen countertops…

C) Granite: igneous rock composed of quartz, feldespar and mica C) Granite: igneous rock composed of quartz, feldespar and mica. Formed by the crystallisation of volcanic magma under the Earth´s surface. It is used for floors, walls, kitchen countertops and sculptures.

D) Slate: is a dark blue or black metamorphic rock that it is formed by the compression of fine clay. It is usually used for floors and pavements.

E)Tuff: is a porous rock that is formed by the cooling of volcanic ash and lava.It is a very good thermal insulator, so it is often used to build walls.

TRUE OR FALSE? Marble and granite are usually extracted as very small pieces of stone. Crushed gravel provides friction because it isn´t smooth or round. Granite isn´t used for floors because it is fragile and breaks easily. Slate is light and porous because it is made of compressed clay. Tuff is used to make homes because it is a good insulating material.

Natural stone Limestone. Sedimentary rock – porous, off-white Marble. Metamorphic rock – hard, dense and resistant to compression Granite. Igneous rock (quartz, feldspar and mica) – very resistant to impacts, compression and erosion Slate. Metamorphic rock – hard, dense, compact and waterproof Tuff– black, porous and thermal insulator Pavement The Pietà, Windbreaks Masonry

1.3.Stone binders Plaster Lime Cement Mortars

A) Plaster: is made from gypsum rock, which is crushed, heated and dehydrated. Plaster dissolves in water, creating a sticky paste that dries quickly. Uses: lining of walls and ceilings, mouldings and sculptures.

B) Lime: produced by heating limestone to 900ºC (calcination) B) Lime: produced by heating limestone to 900ºC (calcination).Mixed with water, it forms a paste which solidifies quite easily. Uses: whitewashing for walls and in mixtures with other building materials.

C) Cement: is a mixture of limestone and clay that has been crushed and heated to 1250ºC. Uses: pipes, pavements, bricks and blocks, mortar and mixtures with other building materials.

D) Mortars: are various mixtures of binders with sand and water.

Stone binders When water is added, there is an exothermic chemical reaction that leads to a setting process. Plaster Obtention: gypsum rock Properties: sticky, resistant to compression and fire Lime Obtention: limestone Properties: sticky, waterproof and resistant to compression Cement Obtention: limestone and clay Properties: very hard and resistant Mortars Obtention: mixtures of binders with sand and water Properties: sticky; hydraulic mortars are water resistant. Bricks with mortar Plastered wall Cement blocks and mortar

1.4. Artificial stone Concrete Fibre cement Hempcrete bricks Terrazzo

A) Concrete: is a mixture of gravel, sand, water and cement A) Concrete: is a mixture of gravel, sand, water and cement. When it is used for structural purposes, a framework can be added (reinforced concrete). Uses: foundations. Reinforced: pillars and floors.

B) Fibre cement: is composed of fibres covered with mortar. Uses: pipes and roofs

C) Hempcrete bricks: made of hemp fibres, along with lime. Uses: construction

D) Terrazzo: made with a mixture of gravel and white cement. Uses: floors

Artificial stone Concrete Obtention: gravel, sand, water and cement Properties: very resistant to pressure, but not to traction Reinforced concrete (with steel bars)  also resistant to traction Fibre cement Obtention: fibres covered with mortar Properties: waterproof and resistant Hempcrete bricks Obtention: hemp fibre, soil and lime Properties: thermal and acoustic insulator Terrazzo Obtention: mixture of gravel and white cement Properties: very resistant Structure with pillars and beams made of reinforced concrete

2. CERAMICS Technology

Ceramics 2.1. General properties Ceramic materials are made from clay. Properties: When clay is wet, it is both soft and pliable, so it can be shaped very easily. Once clay dries, it becomes porous and chemically inert, as well as resistant to high temperatures. © Oxford University Press España, S. A. Technology

2.2. How ceramic materials are made How ceramics materials are made 1. Preparation 2. Mixing 3. Shaping 4. Drying 5. Firing 6. Decoration https://www.youtube.com/watch?v=3YBK5Kdy8VI

A) Preparation: Clay is cleaned and broken into smaller pieces by large rollers. B) Mixing: clay is mixed with water, colouring, temper (increases the plasticity of clay) and flux (reduces the melting point of clay)

C) Shaping: the clay is shaped to its final form.

D) Drying: the clay is dried to eliminate water. E) Firing: this is done in special ovens called kilns at temperatures between 700ºC and 1700ºC

F) Decoration

2.3. Classification of ceramic materials A) Coarse ceramics (water-permeable) Terracotta Earthenware Refractory ceramics

COARSE CERAMICS – water-permeables Terracotta Ordinary clay that is usually a matte red colour. It is hard, rough and fragile. Bricks, roof tiles and pottery Earthenware A mixture of white clay, silica and feldspar. It is fine and smooth, as well as hard. Crockery, decortaive objects and bathroom tiles Refractory ceramics Baked clay and metal oxides. They can resist temperatures up to 3 000ºC. electrical and electronic components

B) Fine ceramics (non-permeable, glass-like properties). Stoneware Porcelain

FINE CERAMICS – non-permeable with certain glass-like properties Stoneware It is made from refractory clay, has a glass-like appearance. It is very compactable and hard Tiles, tubes and bricks Porcelain It is made with kaolin. It is transparent, translucent, compact, acid-resistant and hard Tableware, decorative objects, laboratory materials…

3. GLASS Technology

3. Glass forming techniques https://www.youtube.com/watch?v=M5BIjwv2WxE 1. What is glass? 2. Properties of glass 3. Glass forming techniques Automatic blow moulding Glass casting Drawing Floating Calendering and lamination EL TRABAJO ES VOLUNTARIO, PERO COMPUTA CON UN MÁXIMO DE 2 PUNTOS SOBRE LA NOTA DEL EXAMEN

Glass Glass is made with a mixture of sand, quartz, lime and soda, which is melted in a kiln at temperatures of more than 1 400ºC. Properties: It is hard and smooth, but also fragile. Glass is resistant to weather and chemical agents, as well as a good thermal, electrical and acoustic insulator. © Oxford University Press España, S. A. Technology

3.1. Glass forming techniques Automatic blow moulding Glass casting Drawing Floating Calendering and lamination https://www.youtube.com/watch?v=M5BIjwv2WxE

Glass forming techniques(I) Automatic blow moulding Hot glass is poured into a hollow mould; then compressed air is used to push the glass The mould is opened and the glass object is taken out. Glass casting Hot glass is poured into a mould and allowed to cool. It is used to make ashtrays, containers, bottles, glass bricks for construction

Glass forming techniques (II) Drawing Hot glass is drawn, or pulled, from a tank by using a machine that forms sheets. It is used to make plate glass to make windows, windscreens and mirrors. Floating Hot glass is poured into a tank that contains liquid metal, such as tin. Same applications as drawing. Calendering and lamination Hot glass goes though a system of rollers. It is used to make safety glass.

Write the main characteristics of the different glass-forming techniques and its principal uses.