Block squaring off
Squaring off marble/granite blocks is a first step of vital importance. Using cutting machinery, the rough edges of the block can be removed rapidly and with little waste. Squaring off makes for more ‘uniformly’ shaped slabs. This saves time and money at the marble-working stage for end-users. The blocks are then ready for the next stage: sawing for the production of slabs.
Sawing
Sawing for the production of slabs is performed using diamond gangsaws which enable production to all desired thickness specifications provided by customers. For the production os tiles are used blockcutters.
Diamond Sawn
Is the surface resulting after a block is sawn into slabs using a Diamond Saw (Block Saw, Diamond Wire Saw or Diamond Gangsaw). Once cleaned of the sawing swarf the surface should be smooth probably with some saw marking evident. Diamond Sawing can be carried out on all natural stones.
Gangsawn
An alternative to diamond sawing is to produce slabs using a Granite gangsaw. Cutting is done by abrasion of the slabs using steel blades and steel shot.
The resultant textured surface (once cleaned of the cutting medium) is rougher than diamond sawing and can be used as a non slip surface where low vibrancy of the material is suitable. Gangsawn surfaces can vary from reasonable flat to ones that are heavily styrated depending on the Gangsaw being used.
Gangsawing can also be done with Sandstone and Bluestone although this is less prevalent than Granite Gangsawing.
Resin finishing
Once the slabs have been cut, they must undergo resin finishing – another very important process. Resin finishing is conducted by means of automatic lines. This consolidation procedure provides a means of compensating for defects by filling the small ‘flaws’, pitting or spalling frequently found in such natural materials.
Finishing
Following resin finishing, automated lines are used for all required slab surface finishing operations: polishing, smoothing, brushing, sanding, bush-hammering, rolling etc.
Flamed Exfoliated
Passing a granite slab or panel under an extremely hot flame (1100 degrees Celcius) generally causes the surface to exfoliate with the outermost grains flaking off leaving a rough textured surface suitable for slip resistant external or internal paving. The crystals exposed this way are much darker than a sawn surface despite having no gloss. Flaming is not effective on Marble, Bluestone or Sandstone because of the differing grain structure.
Flaming of edges is generally not done because the loss of grains at the corners will leave a ragged edge. Any edges that are exposed and should also be textured should be bead blasted or left sawn.
Beadblasted
By blasting the surface using various blasting media at high velocity (Steel Shot, Slag, Glass Beads) a range of textured finishes can be achieved that are slip resistant. Bead Blasting can be done on all natural stones.
Panels are able to be masked so that only certain areas are blasted and the remainder remains with the original surface finish such as blasted patterns on a polished surface.
Rubbed
Taking a Diamond Sawn surface and performing an initial rubbing pass to remove saw marks gives a rubbed finish with no sheen. Rubbing can be done to all natural stones.
Honed
Best described as a matte or semi polished finish a Honed finish can be considered to be a partially polished surface.
Varying levels of gloss can be obtained below a full polish from high reflection (close to a polish) to no gloss under normal light (egg shell finish).
Honed finishes are generally used for internal or external paving as they generally have higher slip resistance than a polished finish and are less prone to discernable wear patterns.
Obviously some loss of vibrancy occurs with the lower gloss level and normal practice is to seal any honed surfaces as they are less stain resistant than a polished finish.
Honing can be done to all natural stones.
Honed edges are achieved by Edge Polishing machines or by a Stonemason using hand held polishing grinders and special stones.
Polished
A high gloss finish imparted to Granite, Marble, Bluestone and some Sandstones by grinding with successively finer polishing mediums. This is the most reflective finish available with Natural Stone.
Diamond grinding is normally used to achieve initial flatness and then finer and finer Silicon Carbide grit in a matrix to form a polishing stone is used to level the surface and provide a high gloss surface.
Polishing can be done using a fully Automatic Polishing Line (a machine with 12 or more polishing stations in a line and below which the material is transported on a continuous belt), a Bridge Polisher (Single Head Machine) or a Jenny Lynn Polisher (Floating head on an articulated arm operated manually).
As with honing Polishing of edges is achieved by Edge Polishing machines or by a Stonemason using hand held polishing grinders and special stones.
Polished finishes are normally used for Cladding, Benchtops and low traffic paving (The polished surface of paving can wear in high traffic areas removing the high gloss and leaving tell tale cow paths across the paving).
Pitched Face
Is an extremely rough finish achieved by pitching off using a bolster (hammer) and pitching tool (chisel). This finish can be used on all natural stones but with varying degrees of effect.
Hydrasplit
A finish used on sandstone or Bluestone where the stone is split (in the case of Sandstone along its bed) using a Hydraulic Guillotine. The natural split resulting can cause the face and edges to vary quite considerably.
RockFaced
Starting with Hydrasplit Sandstone or Bluestone, the edges can be split back to a uniform line. Rockfacing reduces the variability of a Hydrasplit face and gives the appearance of a natural or rock finish.
Textured Faces with Chiseled Margins
With split faced or rock faced stone it is possible to chisel a fine margin around the rough face.
This is an effect often used in old Sandstone and Bluestone buildings.
The texture of the margin can be varied depending on the chisel used from plain to lightly combed through to heavily combed. (The degree of) Combing refers to the number and depth of styrations along a given length of the margin.
