Many people who associate with stone assume that it is a permanent
material that does not need maintenance or care. After new stone
is installed, permanent damage often occurs from neglect, incorrect
cleaning methods, and using chemicals that are not formulated for
When stone is purchased, it proceeds thought a four stage process.
The process begins when the architect selects and designs the stone.
The second stage is completed when the stone supplier fabricates
and delivers the material. The third stage is accomplished when
the stone is properly installed, protected, and then grouted. The
final stage entails selecting a proper stone maintenance system.
Understanding stone and the products that are available for stone
care are vital elements for a successful stone maintenance system.
The objective is to establish a customized and long-term
stone maintenance system that covers the stone maintenance cycle.
The cycle includes preventive maintenance, daily maintenance, and
Stone needs conditioning, cleaning, protection, and restoration.
Understanding stone and stone care products are the most important
features in development a successful maintenance program.
How much training and education do employees receive on stone care
maintenance? The answer is usually none.
Today most stone floors as if they are resilient tile. Most stone
vanity and counter tops are cleaned with harsh chemicals as if they
were made of Formica.
A through inspection of the facility will be provided to establish
special stone care techniques for problem areas. Example, how to
maintain stone in an elevator?
Stone is a natural solid formation of one or many minerals. There
are thousand types of stone that have been quarried thought the
centuries. Quarries are located all around the world. A majority
of natural stone comes from Italy, Spain, Turkey, United States,
Mexico, china, Taiwan, India, Greece, canada, France, and Brazil.
The minerals in stone came from the same liquid and gas minerals
that formed the earth. The Earth developed as a massive body of
gas and liquid minerals that slowly cooled and condensed to a solid
care. Through pressure, the Earth's crust began to from and heavy
minerals were forced down to the core of the Earth, where they were
trapped. As the crust got thicker, it squeezed around the inner
core, which created intense pressure and heat from within the Earth.
crystals and other solid forms began to grow from the mineral vapors
that were being released. As the Earth's crust began to expand and
erode, heat and pressure pushed the solid minerals up to the Earth's
surface, which formed colossal rock beds. It took up to a hundred
million years to from some of these beds. Many of the beds are now
used as quarries where the stone is mined.
Most of these minerals can be identified by their color, hardness,
and crystal formation. crystals come in a variety of shapes and
sizes. The wide arrays of minerals are often difficult to identify.
Many stones look very similar to each other; however, they are all
It is imperative to know the exact type of stone that is to be maintained.
Stone is natural and may have adverse reaction to certain cleaning
chemicals and procedures. Most stones are also natural alkalis and
so are dirt and soil; therefore, stone and dirt are attracted to
each other often making cleaning very difficult. This makes the
proper selections of cleaning procedures and chemicals for stone
TYPES OF STONE:
The familiar stone types that are used today are identified through
Sedimentary, Metamorphic, Igneous and Man-made stone.
I. Sedimentary stone came from organic elements such as glaciers,
rivers, wind, oceans, and plants. Tiny sedimentary pieces broke
off form these elements and accumulated to from rock beds. They
were bonded through millions of years of heat and pressure.
Limestone: Mainly consists of calcite. It does not show such
graining or crystalline structure. It has a smooth granular surface.
Varies in hardness. Some dense limestone can be polished. common
colors are black, grey, white, yellow or brown. It is more likely
to stain than marble. Limestone is known to contain lime form sea
Sandstone: Is a very durable formation of quartz grains (sand).
Usually formed in light brown or red colors. categorized by the
most popular sandstone bonding agents such as silica, calcium, clay,
and iron oxide.
Soapstone: A very soft stone made of a variety of talc. It
is a dense mineral that wears well and is often resistant to oxide.
Fossilstone: considered a limestone that contains natural
fossils such as sea-shells and plants.
Travertine: Usually a cream or reddish color. It is formed
through the accumulation of calcite from hot springs. It contains
lots of holes that were formed from water flowing through the stone.
These holes are often filled with synthetic resins or cements. Requires
lots of maintenance if the holds are not filled. classified as a
limestone and a marble.
II. Metamorphic stone originates from a natural from one
type of stone to another type through the mixture of heat, pressure,
and minerals. The change may be a development of a crystalline formation,
a texture change, or a color change.
Marble: A recrystallized limestone that formed when the limestone
softened from heat and pressure and recrystallized into marble where
mineral change occurred. The main consistency is calcium and dolomite.
Ranges in many colors and is usually heavily veined and shows lots
of grains. Hardness rates from 2.5 to 5 on the MOH Scale.
Marble is classified into three categories:
1. Dolomite: If it has more than 40% magnesium
2. Magnesium: If it has between 5% and 40% magnesium
3. calcite: If it has less than 5% magnesium carbonate.
Slate: Fine grained metamorphic stone that is formed from
clay, sedimentary rock shale, and sometimes quartz. Very thin and
can break easily. Usually in black, gray or green.
Serpentine: Identified by its marks, which look like the
skin of a serpent. Most popular colors are green and brown. Hardness
rates from 2.5 to 4 on the MOH scale. contains serpentine minerals
has lots of magnesium, and has an igneous origin. Does not always
react well to recrystallization or diamond polishing.
III. Igneous stones are mainly formed through volcanic material
such as magma. Underneath the Earth's surface, liquid magma cooled
and solidified. Mineral gases and liquids penetrated into the stone
and created new crystalline formations with various colors.
Granite: Primarily made of Quartz (35%), Feldspar (45%) and
Potassium. Usually in dark colors. contains very little calcite,
if any. Provide a heavy crystalline and granular appearance with
mineral grains. It is very hard material and easier to maintain
than marble. Yet, it is still porous and will stain. There are different
types of granite depending on the percentage mix of quartz, mica
and feldspar. Black granite is known as an Anorthosite. It contains
very little quartz and feldspar and has a different composition
than true granite.
IV. Man Made Stones are derived of unnatural mixtures such
resin or cement with the additive of stone chips.
Terrazzo: Marble and granite chips embedded in a cement composition.
Agglomerate or conglomerate: Marble chips embedded in a colored
cultured or Faux Marble: A mix of resins that are painted
or mixed with a paint to looks like marble.
currently, there are many companies around the world that use generic
names to identify different types of stone. This has created a problem
for the stone maintenance industry. The original names were in Italian.
Usually the name consists of two parts. The first part describes
the color and second part describes the name from where the stone
|Dorato / D'oro
Negro Marquina is a black limestone from Marquina, Spain.
Bianco carrara is a white marble from carrara, Italy.
TYPES OF SURFAcE TEXTURES
There are many different types of stone available today. When stone
is ordered, it is fabricated with a particular type of surface. There
are six main type of surfaces that are selected:
Honed: Provides a flat to low sheen gloss. Different levels
of gloss can be selected. This surface is very smooth, but often very
porous. This texture is common in high traffic buildings. Honed floors
should always be protected with Penetrating Sealer because it has
wide-open pores. Honed stone colors are not as vibrant as polished
Polished: A glossy surfaces that wears away with time due to
heavy foot traffic and using improper maintenance procedure. This
surface is very smooth and not porous. The reflectively of polished
crystals brings out the brilliant colors and grains of natural stone.
The shine comes from the natural reflection of the stone's crystals.
The shine is due to polishing bricks and polishing powders used during
fabrication. The Shine is not from a coating.
Flamed: A rough surface that is developed through heat. During
fabrication, the stone is heated up and the crystals begin to pop,
thus forming a rough surface. This surface is very porous and must
be treated with an impregnator.
Sand Blasted: This surface is the result of a pressurized flow
of sand water that provides a textured surface with a matte gloss.
Sawn: A Process performed by using a gang saw.
Bush Hammered: A pounding action that develops a textured surface.
The degree of roughness can be selected.
Regardless of the type of surface to be maintained, all stone should
be protected with sealers.
As discussed previously, stone was formed from different types of
natural minerals. Marble's main consistency is calcium. calcium carbonate
is the natural source that bonds the stone. certain additive minerals
blended into during formation to customize these brilliant colors.
The additive minerals are also color developers present in granite
and other natural stones.
||Biotite, Hornblende, carbon
||Variety of minerals
||Mica, chloride, Silicate
||Brown, Green, Black,
||Black, Brown, Green
||Yellow, White, Pink,
||Metallic Grey or
||Green, Yellow, Brown,
||Black, Brown, or
Minerals have a variety of crystalline properties. A different has
a different color. For instance, Augite (listed above) has different
crystalline properties. Each property has its own color. Stones brilliant
colors and various crystal formations developed when different mineral
properties blended together along with the integration of temperature
The veins and color grains of marble were liquid minerals that flowed
through the stone when the Earth heated up. The intense heat softened
the limestone to allow the liquid to flow through it. When the Earth
cooled, the mineral flow stopped and gradually hardened to its state.
The delicate colors of stone often can altered by the improper use
of cleaning chemical, mopping with dirty solution, using chemicals
that are not designed for stone care, and sunlight can fade the color
of natural minerals.
REFLEcTIVITY OF STONE
Stone contains natural crystals. These crystals reflect light to provide
a shine on the surface. When the crystal care dull, crushed, or broken,
they cannot reflect light evenly. For Example, when the lens of a
flashlight breaks, it cannot reflect the light that is being emitted
form the bulb.
Polished stone floors become dull when heavy foot traffic along with
sediment erodes the crystals. Normal footwear does not cause the main
damage, sediment and grit do. The sediment and grit that lies on the
stone surface is the main enemy of stones crystal. The damage to the
crystals occurs when the pressure from the shoe forces the sediment
to abrade or fracture the crystals.
The only safe way to restore and sharpen the crystal is to polish
them with diamond abrasives or polishing powders. The life span of
crystal can be extended can by administering a through dust mopping
program with proper moping and maintenance system. Extensive entrance
matting is extremely important because it keeps exterior sediment
from entering a building.
THE HARDNESS OF STONE
Marble is a relatively soft stone. On a measurement of hardness of
(MOHS), marble is approximately a three out of ten. Marble is made
of calcium, just like your teeth. If you eat something to hard you
will break your tooth. If you eat a lot of sugar you will get a cavity.
Stone reacts the same way. If an improper chemical is applied to the
surface, corrosion will begin to from cavities in the stone.
Listed below is the famous Measurement of Hardness (MOHS) Scale for
stone. This is a guide developed in the 1800's, which helps evaluate
the strengths and weakness of the stone being used. For example, softer
stone would require less active chemical and a more frequent dust-mopping
MEASUREMENT OF HARDNESS ScALE
||calcite (Most Marbles)
The objective of the MOH's Scale is to measure stone resistance to
hardness. When sediment and grit harder than the surface, they will
scratch and harm the stone. For example, a piece of hard plastic is
about a 2.0. It will not scratch #3 calcite (Marble). However, a piece
of sand that measures a 6, will scratch #3 calcite but will not scratch
#7 Quartz which is Granite. The harder the stone, the more resistant
it is to abrasion. Exterior sediment that is tracked in to buildings
approximately measures from 3.0 to 7.0.
UNDERTSTANDING STONE MAINTENANcE cHEMIcALS
In the stone maintenance industry there are two types of chemicals
that are utilized, water-based and solvent-based.
Solvent-based chemicals do not contain any water do not register a
PH balance. These ingredients are only soluble in other solvent. Some
examples of solvent chemicals are paint thinners, most penetrating
sealers (impregnators), D-Limonene, and alcohol.
Water-based chemicals are chemicals that contain water and have a
PH balance. chemicals mixed in water are soluble in water. There are
a water-based chemical such as neutral cleaners, ammonia, bleach,
and most chemicals that have a PH balance.
In order to determine the different between solvent and water based
chemicals, read the Material Safety Data Sheet (MSDS). Most solvent
have flash point and can ignite. Most water-based chemicals do not
have a flash point unless contain a solvent ingredient to add strength
to the product. For example, many degreasers contain D-limonene. In
most stone care situations, if a stain or coating is water-based,
then water-based chemicals are needed to remove it.
Listed below are samples of the two types of chemicals:
|All purpose cleaners
It is advisable to use water-based chemicals. The reason is due to
the environmental concern that solvent-based chemicals are harmful
to our environment. Water based chemical are usually more user friendly.
Remember to always wear proper protective gear when using any chemical
and them all out of the reach of children.
UNDERSTANDING PH BALANcES
PH is a unit of measure to determine the alkalinity and acidity
of a solution. PH has been defined as either the "power of Hydrogen"
or "Pre-existing Hydrogen". It is rated on a scale of 0
to 14. 0 to 6.5 being acidic (Hydrogen) and 7.5 to 14 being an alkali
(Hydroxide). 7 being neutral.
|Acid Bowl cleaners
|Most fruit Juices
||Most all purpose
& household cleaners.
|Many household bathroom
|Dirt and soil Many
Most stones used today are sensitive to both acidic and alkali cleaners.
One reason is due to the fact that most stones are classified as hydroxides,
which classifies them as natural alkalis. Acids will burn most stones
by dissolving the bonding agent that together. Alkalis usually do
not damage stone as quickly, however, they will cause deterioration.
The corrosiveness of acids cannot always be measured with the pH scale.
In most instances, the lower the pH number the stronger the acids.
A solution with a pH level of 1 is usually stronger than a solution
with a pH of 4. However, there are some acids with a higher pH that
are stronger than an acid with a lower pH.
On the alkali side, the higher the pH number the stronger the alkali
should be. A solution with a pH balance of 12 is usually stronger
than a solution with a pH of 9. When using an alkali cleaner, never
use hot water because it may create a stronger alkali with adverse
Understanding pH balance will help select the proper chemicals that
can be used on stone. However, a main factor to remember when selecting
a stone maintenance chemical is the activity level. For example, most
neutral cleaners have a pH balance of 7; however, some neutral cleaners
are stronger than others because they have higher activity levels.
There are many neutral cleaners that are not active enough to thoroughly
clean a stone's surface. There are also an abundance of neutral cleaners
that are too active for stone to endure.
UNDERSTANDING THE STONE MAINTENANcE cYcLE
Stone is a neutral material. It should be taken care with proper
maintenance procedures. Once the stone is installed, it will always
go through a natural life cycle, precise maintenance schedules must
be developed to care your type of stone.
Two main factors that should be considered when designing a maintenance
program are the hardness and absorbency of the stone. These factors
will help decide which chemicals, pads, brushes, and equipment are
necessary to maintain the stone.
The Stone Maintenance cycle is comprised of three segments:
I. Preventive Maintenance
- Protecting the interior of the stone with a Penetrating Sealer.
- Proper walks-off entrance matting.
- Understanding your stone, chemicals, and procedures.
- Dust Mopping with clean rayon mops.
- Properly laundering and caring for maps.
- Wet mopping with a mopping program.
- Repairing pits and cracks with epoxy or glues.
- Prompt spill pick-ups to prevent etching and staining.
- Powder polishing to receive polished finishes.
- Reabsorbing stains with poultice powders.
- Resurfacing the stone with a diamond abrasive program to remove
scratches, abrasions, and traffic patterns.
- Deep cleaning the pores of honed, flamed, or ground floors.