After the discovery and promotion of Sukabumi stone, this material became very popular for the last decade in swimming pools. It was sold under various names;
Bali Green
Sukabumi (premium when sorted by size and quality)
Pedra Hijau.
This volcanic stone was formed as a grey Andesitic tuff and deposited in a presumably freshwater environment. The deposit is quite thin about 50-100 meters thick only.
After deposition, it was covered by andesite flows and placed in a near vertical position flanked on both sides by andesites.
Later hydro-thermal (hot fluids coming up through the stone) alteration of the original tuffaceous stone, with chloritic fluids changed the stone into a green appearance. The hot fluids also contained ample iron and manganese ions, these resulted in frequent iron-rich filled fractures and ample black manganese nodules.
This geological process intensifies going down into the deposit. Frequent fracturing limits the size of recoverable stone to 10/10 and 20/20 cm tiles; rarely 30/30 cm can be cut. Pervasive iron staining throughout the deposit, increasing with depth causes many black brown and yellow staining. After exposure outdoors or inside the pool, often more than 50% turns brown or black.
Basically, only the upper part of the deposit can be used on a commercial scale, the risk of poor quality material increases with depth, sorting is not really possible and for the end-user it becomes a gamble how it will finally look in the pool, with a big risk it will deteriorate within a year or two.
Lots of nonsense is written by sellers about the health aspect of the zeolites in the stone. Firstly there is almost none or very little zeolite in the stone, secondly, no medical evidence exists for such a claim.
Volcanic Green or New Sukabumi
This also is an andesitic tuff, but epithermal alteration took place in the magma before the material was deposited by volcanic eruption as a welded tuff possibly also in a lake. The deposit has been laid down in thick layers, varying in thickness from meters to tens of meters thick. The overall deposit is very big covering a very large area and with a thickness of several hundreds of meters.
After deposition no further alteration took place, so the stone reflects its origin and was not influenced by pervasive iron/manganes/chloritic percolating fluids. This allows quarrying of large size blocks of several m3 along the bedding plane.
Cutting of slabs long 2-3 meters and with a height of 150 cm, allows recovering of all required sizes. Stone losses are limited as fractured veins are very rare and mainly restricted to the top part of the quarry.
Material is identical to the original Sukabumi, but with a very distinct geological history, The stone is close in colour to the original type, but much more stable and available without risk about future discouloring from enclosed iron.
Stone can be used inside the pool, coping, flooring, cladding, and even as countertop material. Standard finishings are: Sawn only, rough honed, bushammered, and honed.
Like all Natural Stone, there is always a variation in the texture of the material, colour, and other potential problems. HSN always tries, with normally great success, to avoid such issues, but if a mistake has been made, we aim at correcting it properly.
