Black Galaxy Granite : Factual Information For Users Worldwide
Black Galaxy granite is undoubtedly one of the world's most popular and successful granites and has been exported to every continent. It is a fine to medium-grained, black gabbric anorthosite with golden-yellow sparkling broncite scales. Internationally this stone may be nominated as a granite and for the US and Chinese markets this is correct however in Europe the stone must be nominated as a gabbro because the European Standard EN 12440 (Natural Stone, Denomination Criteria) demands a scientific terminology determined with a petrografic examination according to EN 12407 and 4.2 of prEN 12670.
Black Galaxy Granite Quarrying Region
The quarrying area is Chimakurthi, Ongole, Andhra Pradesh, South India (approx. 350 km north of Chennai) where one would find about 50 Galaxy quarries however not all operate 12 months of the year.
The original Black Galaxy quarry was opened by ourselves in the very early 1980s and is still known to this day as Star Galaxy Granite. The myth that Japanese businessmen discovered Black Galaxy granite in 1989 is completely erroneous since quarrying had already been under way for several years! When other Indian quarrying companies saw the success we had with this material it started a rush for quarrying licences in the Ongole area. There are now many Black Galaxy quarries, some are small family run operations of a couple of acres and some are very large, commercial enterprises with many employees over twenty acres. Obtaining accurate figures of those directly employed in Galaxy quarrying production and processing in the Ongole area is difficult however estimates put it at around 20,000 in the quarries and 12,500 people in the local processing plants with maybe another 5,000 in support industries.
The actual Galaxy granite quarrying area is estimated to be some 1,000 acres and approximately 70% of all the quarried rough block exported from Chennai port goes to China for processing and especially it is believed 95% of small blocks. Overall these figures are not at all accurate since much local trading of blocks, slabs and tiles goes totally unreported therefore expect to find discrepancies to the above.
Large blocks, i.e those 2400+ x 1200+ x 1000 mm the ones preferred by processors to make large random slabs, make up approximately only 40% of the total production of about 8,000 cubic metres per month. It is important to note that the larger the block the more expensive the cost therefore processors do not purchase large blocks to make the very popular floor and wall tiles. We have seen figures claiming that 20-25,000 CBM (cubic metres) of black galaxy is quarried each month however we have been unable to verify this.
Not all Black Galaxy granite is the same and different markets prefer different types. The gold specks are due to the presence of ferrous rich Enstatine (Bronzite) and can be broadly divided into three types based on the size of the gold coloured specks as:
1. Large grained Black Galaxy
Also Black Galaxy granites have slightly varying background colours:
1. Dark Black
NOTE: For large projects it is essential to source the Black Galaxy from the same quarry supply since mixing background colours will be very noticeable.
Some Black Galaxy granites may require an epoxy resin application since they may appear to have a slightly open veining. The integrity of the granite is not affected with the epoxy applied solely for a visual effect to give it the smooth finish demanded by many purchasers. It is most unlikely that any type of sealer can successfully be applied to this granite.Black Galaxy Quality Standards
Grading standards for Black Galaxy Granite is generally accepted to be as follows:
1. Black Galaxy Q1 First Choice: Slabs and tiles clean of any visible veining
These lines do not affect the integrity of the material and are usually only visible from behind or very close up.
Black Galaxy Granite Usage
Whilst Black Galaxy is used for many, many kitchen countertop projects and bathroom vanity tops the overwhelming majority of Black Galaxy is processed into calibrated tiles, paving or construction projects. Obviously a polished surface is the most common surface finish to bring out the best colours in the granite plus the glossy surface gives a great contrast to all types of accessories such as taps, sinks or cabinet door handles. Galaxy is also suitable for flamed (thermal), honed, river-washed, leather and brushed finishes. To learn more about these please go here (Opens in a new window).
Black Galaxy Granite Durability
It is very hard-wearing, very durable and highly moisture resistant with a low maintenance cost however when used as a flooring material in high traffic areas, like all flooring materials, it can be subject to scratching from road and pavement dust and the worst of all is sand dust and that will have an effect on any surface!
Black Galaxy Granite Supplies
Full Container Loads (FCLs) Only
An FCL Of Natural Stone Will Hold Between 18-27 Tonnes Depending On The Port Of Unloading