An Introduction to
Natural Phyllite Architectural
Stone
Who are SSQ & Riverstone?
•
SSQ Group was founded in
1983
•
Producers and exporters of
natural slate from Spain,
Argentina and Brazil
•
Specialists in finest quality
imported slate & phyllite
•
Market leader in UK; exports
to Europe and worldwide
Who are SSQ and Riverstone?
•
Riverstone Ltd (part of
SSQ Group) was
established in 2003
•
Recently expanded
product portfolio to
include full Riverstone
Architectural range
•
Due to quarry ownership
we can always fulfill our
promises and ensure
high quality control
procedures are in place
Objectives
•
To explain the formation and extraction of phyllite
•
To demonstrate why phyllite can be an excellent alternative
to slate
•
To highlight why its properties make it suitable for
architectural applications
•
To help provide sufficient information to ensure problem free
specifications using natural phyllite architectural and flooring
products
Contents
•
Introduction to phyllite – geology, extraction and source
•
Advantages of phyllite and problems occurred using inferior
products
•
Natural phyllite testing & standards
•
Natural stone comparison table
•
Stone protection
An Introduction to Natural phyllite
Definition: “Phyllite is from scientific Latin and means ‘leaf-stone’
phyllite is a medium grey stone.”
•
Phyllite is a metamorphic stone.
•
Phyllite can be split by hand.
•
Phyllite is formed from two other types of stone: slate and
schist.
•
Phyllite has a visible sheen owing to its exposure to extreme
heat and pressure
•
Phyllite tends to have a corrugated surface which can be
polished to achieve a smooth surface.
An introduction to natural phyllite
Source: San Luis quarry located in Argentina
• Total ownership by SSQ
Group.
• All quality control done by
trusted methods at source.
• Formed over 600 million
years ago.
• Shares many characteristics
with Cornish slate due to
the tectonic plate
movements.
The formation of phyllite
There are 3 key classifications of natural stone, each is formed in
different ways and is comprised of different minerals.
Metamorphic Rock
Rock that has been physically altered by
heat and/or pressure; most commonly
quartzite, slate, marble and phyllite.
Sedimentary Rock
Phyllite
Limestone
Rock formed by the hardening of
material deposited in some process;
most commonly sandstone, shale, and
limestone.
Igneous Rock
Formed when molten (melted) materials
harden through crystallisation; most
commonly granite and basalt.
Granite
The formation of phyllite
Phyllite is a fine-grained metamorphic rock, formed from the
compressive pressure from both the sea and the earth’s core.
phyllite
•
Varying degrees of heat and pressure contribute to the
stones formation and strength
•
Due to the fine grain and high compression of phyllite,
the result is a very dense stone
The extraction process
Phyllite is always quarried from above and below the quartz vein.
Quartz vein
Why quarry around the quartz vein?
1. Acts as a compressive barrier
2. Ensures the highest quality of stone
The extraction process cont.
The stone is extracted in steps using a diamond cutting wire.
Quarry rock face
Why quarry in steps?
1. Minimises wastage
2. No need to use explosives
Advantages of natural phyllite
• High density
• Very low porosity
• Durable
• Exceptional strength
• Versatile
• Minimum maintenance
(once laid and sealed
properly)
Advantages of natural phyllite
• Non combustible
• Not susceptible to acid attack
thus pollution resistant
• Natural product
• Long life expectancy
Problems from using an inferior natural stone
to phyllite
• Can be poorly calibrated
• Can be poorly gauged
• Easily absorb stains
• Efflorescence (salt leaches from material)
• Rust (leaching pyrite)
Problems from using an inferior natural stone
to phyllite cont.
• Has negative reactions to the freeze-thaw cycle
• Limitation on surface finish (due to low density)
• May disintegrate (mineral properties react)
• May distort under intense heat
Testing & Standards
6 main types of tests for natural stone:
Type:
Density; Kg/m3
Description:
Measured against water 1,000, higher the density the
better.
EU Test:
BS EN 1936
Type:
Water Absorption, %
Description:
Checks for water absorption in stone, lower is better.
EU Test:
BS EN 13755
Type:
Modulus of Rupture, MPa
Description:
Measures the maximum load the stone can withstand,
higher is better.
EU Test:
BS EN 12372
Testing & Standards cont.
6 main types of tests for natural stone:
Type:
Abrasion Resistance
Description:
Represents the stone’s surface to wear, higher is better.
EU Test:
BS EN 14157
Type:
Freeze Thaw Cycle, Mpa
Description:
Measures the effect of extreme changes in weather,
higher is better.
EU Test:
BS EN 12371
Type:
Slip Resistance
Description:
Tested in wet and dry conditions, higher is better.
EU Test:
BS EN 14231
Testing & Standards cont.
Riverstone Test Results
EU Equivalent
Test Type
Result
(mean)
BS EN 1936
Density, Kg/m3
2760
BS EN 13755
Water Absorption, %
0.49
BS EN 12372
Modulus of Rupture, Mpa
40.53
BS EN 14157
Abrasion Resistance
23.5
BS EN 12371
Freeze Thaw Cycle, Mpa
37.49
BS EN 14231
Slip Resistance: Honed (dry/wet)
63/32
BS EN 14231
Slip Resistance: Brushed Antic (dry/wet)
69/50
Tests have been conducted by Sandberg Consulting Engineers
Stone comparison table
BSEN Test
Riverstone
Kirkstone
Sea Green*
Khatmia*
Tropicale*
Material
Phyllite
Slate
Marble
Granite
Source
Argentina
UK
Egypt
S. Africa
Density, Kg/m3
2760
NR
2690
2640
Water
Absorption, %
0.49
2.25
0.35
0.11
Modulus of
Rupture, Mpa
40.53
11.32
12.48
18.8
Abrasion
Resistance, mm
23.5
12.2
17
13.2
Freeze Thaw
Cycle, Mpa
37.49
NR
NR
NR
Slip Reisitance
Polished
(dry/wet)
63/32
27 (wet)
NR
NR
Slip Resistance
Riven (dry/wet)
69/50
68 (wet)
NR
NR
* Information has been taken from the corporate websites
Installation - flooring
• The main methods of fixing phyllite flooring are:
Mortar (thick bed) method
• Fix the floor tiles in place with a concrete slurry mix
Adhesive (thin bed) method
• Fix the floor tiles in place with a proprietary adhesive
Grouting
• Tiles must be firmly set in the mortar or adhesive before
commencing grouting. Specialist resin based and cement based
grouts are available from a variety of suppliers
Under floor heating
• Phyllite retains heat well and is suitable for use with under floor
heating.
Installation - cladding
• There are various fixing methods depending on where the
cladding is being applied and the density of the pieces of phyllite
• For very dense phyllite cladding the main considerations are:
DEAD LOADS – actual weight of the stonework. APPLIED LOADS
– wind pressure & suction, window cleaning equipment & any
thermal or structural movements that may occur
• For phyllite used as thin cladding, there are various fixing
methods. It is best to check BS 8298: 1994 (Code of practice for
design and installation of natural stone cladding or lining) before
a final selection is made.
• Fixing systems advice and suppliers:
Amare Stone - http://amarestone.com
Halfen Limited - http://www.halfen.co.uk/
Ancon Building Products - http://www.ancon.co.uk/
Protection (Stone Sealing)
Helps to prolong the life of the stone;
• Helps prevent marks and scratches
• Protects against damaging chemicals
An example of a sealed floor is below:
* Some stone sealers will alter the colour of the stone e.g, make
it darker. It is always recommended that you test the sealer on a
sample first or seek advice from the seller. There are many
sealants ranging from water to oil based giving matt and gloss
finishes. An example of a gloss finish sealant is LITHOFIN.
Installation – British Standard References
Wall and floor tiling
• BS 5385 - Wall and Floor Tiling. Code of practice for design and
installation
• BS 8000: Part 11 – Workmanship on building sites. Code of
practice for wall and floor tiling
Cladding
• BS 8298: 1994 – Code of practice for design and installation of
natural stone cladding and lining
• BS 6213: 2000 – Guide to selection of construction sealants
Cladding
• BS 8298: 1994 – Code of practice for design and installation of
natural stone cladding and lining
Different types of applications
Interior Flooring
Exterior Flooring
Different types of applications cont.
Window sills
Slabs
Different types of applications cont.
External Wall Cladding
Internal Wall Cladding
Different types of applications cont.
Roofing
Thank You