AMACE BT1-Natural Stones (copy)

rock

is a natural material that is composed of an aggregate of

one or more minerals, volcanic glass, or organic

materials (e.g., coal, shells);

stone

is a piece of rock

that is used for a specified function (e.g., building stone,

gravestone, gemstone, cobblestone streets, pumice

stone).

Sedimentary Rocks

are materials composed

of materials weathered from pre-existing rock.

bedding

Sedimentary rocks commonly have a layered

appearance due to grains of different

composition, color, or size depositing at

different times.

Igneous Rocks

form from the solidification of

molten rock.

Intrusive igneous rocks

are composed of

crystals that are large enough to be seen with

the naked eye because these rocks cooled

slowly, deep within the Earth thereby allowing

time for the crystals to grow.

extrusive (volcanic) igneous rocks

they cool very quickly after they erupt from a

volcano, and so are composed of microscopic

crystals. Most of them make poor

building stone because they may be weak,

cracked, inconsistent in color, and/or contain

large pores.

Metamorphic Rocks

form from when pre-

existing rocks are exposed to elevated heat and

pressure.

foliation

The directed pressure that is commonly

associated with metamorphism reorients

elongate or flat minerals to be parallel to each

other, thereby defining layering in the rock

gneiss

Under more extreme metamorphic conditions

minerals may segregate into distinct light and

dark colored layers forming a distinctly banded

rock called____

CRYSTALS

are individual minerals that have grown in

place to form a rock. In igneous rocks they are minerals

that crystallize from the solidifying magma/lava.

GRAINS

are pieces of pre-existing rock or organic

material (e.g., shells) that have been cemented together

to form a sedimentary rock.

breccia

If a rock shatters/breaks but the fragments do not travel

far (e.g., avalanche or rock slide) then the grains of rock

will tend to be irregular, jagged, and angular. Once

cemented, these angular clasts (rock fragments) form a

rock called ______

Rounded Grains (Pebbles)

fragments of

mechanically weathered rock that have had their rough

edges smoother by abrasion during transport in water

(river or beach environment)

Angular Grains

fragments of mechanically

weathered rock that have not been abraded

Ooids

a special form or spherical rounded grain of

calcite that forms by accreting like a snowball as they roll

around on the shallow seafloor due to wave energy)

Crystals

cleavage fragments of minerals such as

calcite, halite, and feldspar; growth crystals of minerals

such as quartz

APPEARANCE

clearly an aesthetic matter which is not

amenable to scientific testing. However the geologist

can play an important role in determining the amount

of variation which may be encountered in the color

and texture of stone. Being a natural material ,many

building stones will vary in colour,even when obtained

from a single bed.

STRENGTH

not quite as important as it

may at first appear. In most modern buildings although

built with natural stone,the outer stone wall is in fact

only a cladding consisting of thin sheets of stone,normally

between 40 and 100mm in thickness fixed to the concrete

shell of the building with corrosion resistant metal

fittings. Even where stone is used for the outer part of a

cavity wall ,as in house building ,the load is essentially

only that of the wall itself.

DURABILITY

'the measure of the ability of natural building

stone to endure and to maintain its essential and

distinctive characteristics of strength, resistance to

decay and appearance, with relation to a specific

manner, purpose and environment of use'.

CRYSTALLIZATION TEST

Used for limestones and some sandstones, this is based

upon 19th century tests for frost susceptibility.

It involves the determination of the loss of weight of a

sample after it has undergone 15 cycles of alternately

being soaked in a solution of sodium sulphate and then

dried in a humid oven.

SATURATION COEFFICIENT AND

POROSITY

Also originally designed as a test for frost susceptibility,

the saturation coefficient is defined as the ratio of the

volume of water which can be absorbed by a sample, to

the total volume of pore space in that sample.

RUBBLE

Consists of rough fragments of broken stone that have

at least one good face for exposure in a wall.

Any broken pieces of brick, stone, concrete etc. resulting

from demolition work and building waste; used as fill and

hardc0re.

DIMENSION STONE

Natural stone block, cut stone; a piece of natural stone

which has been cut into rectangular blocks for use in

ashlar masonry.

It is quarried and squared stone 2” or more in length and

width and of specified thickness, used commonly for wall

panels, cornices, copings, lintels and flooring.

FLAGSTONE

A flat stone slab used for paving, flooring and horizontal

surfacing.

CRUSHED STONE

is used as aggregate in concrete

products.

Pebbles

are generally considered larger than granules

(2 to 4 millimetres diameter) and smaller than cobbles

(64 to 256 millimetres diameter)

ARGILITE

It is formed from clay, dark blue with faint shades of

green.

GRANITE

is a light-colored igneous rock with grains large

enough to be visible with the unaided eye. It forms from

the slow crystallization of magma below Earth's surface.

LIMESTONE

A sedimentary rock composed primarily of calcium

carbonate (CaCO3) in the form of the mineral calcite. It

most commonly forms in clear, warm, shallow marine

waters. It is usually an organic sedimentary rock that

forms from the accumulation of shell, coral, algal, and

fecal debris.

TRAVERTINE

is a sedimentary rock, formed by the

precipitation of carbonate minerals from solution in

ground and surface waters, or geothermally heated hot-

springs.

MARBLE

Metamorphic rock, are crystallized limestone forming

into carrara, parian, onyx and Vermont.

SERPENTINE

Typically, olive green

to greenish black but impurities may color the rock.

Used only for interiors due to weathering

SANDSTONE

Class of rock of cemented silica grains with texture

ranging from very fine to very coarse. Colors vary from

buff, red and light brown.

SLATE ROCK

Slate is a fine-grained, foliated metamorphic rock that

is created by the alteration of shale or mudstone by low-

grade regional metamorphism. It is popular for a wide

variety of uses such as roofing, flooring, and flagging

because of its durability and attractive appearance.

PANELING

Thin slabs of stone cut to dimension and thickness to

cover back up walls and provide finished exterior and

interior walls.

ASHLAR MASONRY

Masonry blocks or facing stone which has been

dimensioned, squarely dressed and laid in bonded

courses with narrow joints.

Random Ashlar

Ashlar masonry laid without

regular courses but with an overall effect of

horizontal orientation

Coursed Ashlar

Ashlar masonry laid out in

courses of equal height; blocks of various sizes

may be combined to make up the height of the

course

RUBBLEWORK

Random & no attempt to produce an orderly course

either horizontal or vertical.. Small spaces are filled

with smaller stones.

Coursed Rubble

Fieldstone or roughly

dressed stone, with or without mortar,

assembled to give a effect of courses

Uncoursed Rubble

In this type of masonry,

stones are not arranged in a course, i.e. the

stones are not placed in a horizontal layer

rather just stacked over one another

Fieldstone

Stone found on the ground (i.e.,

notquarried) that is a suitable size and shape

for use as drywall or rubble masonry

TRIM

Stones cut for specific purposes

POLISHED

A shiny glossy surface is achieved by using diamond

abrasives grit followed by polishing powder. The surface

is very smooth and has a mirror-like effect. Polished

stone is not porous and has higher resistance to humidity

and chemicals. Typically used for internal floorings.

SANDBLASTED

A matte textured surface with no gloss as a result of a

pressurised flow of sand and water. Typically used for

exterior walls.

HONED

Diamond abrasives are used for honed finishes as well.

The surface is smooth, non-reflective and is more

porous, unlike a polished finish. Typically used at both

internal and external areas with less exposure to

chemical or moisture.

ABRASIVE

A flat, non-reflective surface with no gloss. Typically

used for areas exposed to weather such as entries,

foyers, etc.

EXFOLIATED (FLAMED)

A rough and very porous surface that is produced by

applying a high temperature flame to the surface of the

stone causing crystals to pop. Typically used for external

areas where slip resistance is prioritised.

NATURAL OR CLEFT

Typically, it is the absence of treatment to leave the

stone in a natural condition.

stonework

any part of a building, structure, cladding or paving,

which incorporates natural stone as a primary material;

construction and detailing in stone

natural stone

stone which has been quarried, cut, shaped and dressed

for use in the construction industry

rustication

in masonrywork, decorative rebates or sinkings around

the edges of individual stones to emphasize joints and

give articulation to the surface; especially prevalent in

Renaissance architecture

stonework finish

the various factory or tooled treatments applied to the

stone surfaces of a building, or natural stone slabs