|
Standard sizes of Marbles
are
TILES
| Sizes |
Thickness |
| 305X305 mm,
457x457 mm 300x300mm, 400X400 mm |
10 mm, 12 mm, 18
mm, 20 mm 25 mm, 30 mm, 40 mm |
| 600X600 mm |
18 mm, 20 mm 25
mm, 30 mm, 40 mm |
SLABS
| Sizes |
Thickness |
| 250x75 cms |
18 mm, 20 mm, 30
mm, 40 mm |
| 250x130 cms and
above |
18 mm, 20 mm, 30
mm, 40 mm |
| 280x160 cm |
18 mm, 20 mm, 30
mm, 40 mm |
Parameters definition
:
Polished - To smooth or
brighten a surface increasing the reflective quality and luster by chemical or
physical processes. Generally gloss levels should be + 90 as measured by a
gloss meter. To achieve this, final polishing should have been done by latest
Italian/ French machines using imported abrasives.
Buffing: Using a
non-abrasive pad attached to a machine, which rotates the pad in a circular
fashion over the stone, generally between 150-300 RPM. Polishing formulations
containing micro-fine abrasive materials are used with buffing to produce a
more reflective gloss on the surface of stone. Waxes are also used with
buffing to enhance the gloss of polished stone.
Honed : To grind a
surface with a high grit material to a uniform specification without producing
a reflective surface.
Sawn - i.e. unpolished. It is
not advisable to buy this way because : floor polishers do not give as good a
polish as factory machine polishers. many defects are not visible easily
before polishing.
Calibration : To grind a
surface with a high grit material to a uniform surface to maintain the
thickness variation.
Gangsaw : To grind two
sides of the stone surfaces with a high grit material to a uniform
specification without producing a reflective surface.
Shade variation - Slabs /
tiles should be sorted to ensure uniformity of shade. Normally, any colour can
be sorted into three shades. Sorting is simple -just lay all the material on
the floor and look from different directions.
Colour patches - These are
darker or lighter patches or bands of single colours due to mineral
localisation.
Scratches : The marring
of the surface caused by physical trauma such as small stones or sand embedded
in shoes scraping across a marble floor.
Staining : The
absorption of foreign pigments or oils into the porous stone causing
discoloration.
Double color - Sometimes two
different grain sizes occur in the same slab, giving the appearance of a
double colour.
Free lengths : i.e. lengths
varying randomly while width is constant are also very attractive. Choose the
widths as per the expected floor area. Buy random lengths and cut at your site
to fit.
Flatness Tolerances
A 4 dimension in any
direction on the surface shall determine variation from true plane, or flat
surfaces. Such variations on polish, hone, and fine rubbed surfaces shall not
exceed tolerances listed below or 1/3 of the specified joint width, whichever
is greater. On surfaces having other finishes, the maximum variation from true
plane shall not exceed the tolerance listed below or + 3 mm of the specified
joint width, whichever is greater.
Polished, honed or fine rubbed
finishes... + 0.5 mm Sawn, Calibrated, 4-cut and
6-cut.... + 1 mm
Edges also can be chamfered /
bevelled. Chamfering removes whiteness and chipped edges. This looks very
good. Chamfering is a simple process in which a polishing brick is run at an
angle of 45o.
DIAGONAL OUT
DIAGONAL OUT MUST NOT BE MORE
THAN 1MM FOR TILES. IN SLABS IT VARIES.
Quality Details :
Polished Marble
a. One Side Fine Mirror
Polished. b.
Gangsawn/Cutter side c. Thickness variation is + 0.5 mm to 1 mm depending upon
Tile/Slab.
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