Three faces of the sustainable stone
As a building stone, Hopealoimu stone is a traditional and durable material: it has lasted in outdoor structures for 40 years. Due to a generous quartz content, the stone is highly resistant to wear: it does not become brittle in freezing temperatures, does not decompose in the industrial environment and does not contain rusting minerals.
From Hopealoimu-stone three different types of surface can be made. Smooth sawn, tophaceous undulating split surface, as well as inimitable block surface. That is, a combination of most diverse items and fireplace corners can be made from the same stone. By combining the stone’s various surfaces, spectacular items can be achieved. The processing of the building stone is simple: cut-off can usually be performed with a hammer and the rounding of stone edges with a grindstone. Due to the good processability of the stone, the construction stone objects can be finished in a flexible way even on the site.
Uses of building stones
- wall claddings: SL, SLA
- indoor floor coating: SLA
- terraces, patios: SLA
- interior stairs: SL
- fireplace cladding: SLA, MLK8
- Plinth cladding: LL2, SLA
- yard tiling: LL1
- walls, embankments: MLK13
- masonry stone and decorative arch
The crystals are shown as dark dots in the smooth sawn surface, and the growth rings form a pattern similar to wood grain on the Hopealoimu stone surface. The finished and impressive sawn surface is ideal as an interior material. Installation of sawn tiles is easy – they are installed like clay tiles. Products:
- Saw plate blank (SLA) is variable in size, natural edged stone slab, the edges of which can be easily shaped with a hammer. Slab thickness of 10 mm. The saw-plate blank has been used for a sauna wall (Figure 2) and for a log cabin floor (Figure 4).
- Saw plate (SL)is a fixed saw plate with thicknesses of 10, 20 and 50 mm. The thickest saw plate is used on stone benches. Saw plate has been used in the hallway by varying the grain direction (Figure 3)
When the Hopealoimu stone is split in the grain direction, a shiny and wavy split surface is achieved. It is suitable as cladding material for interior and exterior applications:
- A cladding plate (LL2) is a plate split from both slope surfaces, the edges of which are free-form. The thickness is 15-30 mm.
- Paving plate (LL1) is a natural plate such as a cladding plate but their thickness is 30-60 mm and the size of 8-40 dm2. The paving plate strips can be split with a hammer from which yard benches can be masoned. The yard plate has been used in the garden (Figure 1).
Fractured block surface is the edge of the slab, which emphasises the stone layering. Masonry mortar with an accelerator is used in the masonry of a fractured surface.
- Muurilohkokivi (MLK13) The wall block stone (MLK13) is a material of cladding masonry. Both edges of the stone are fractured; in addition, one edge can be sawn. Thickness of 40-60 mm, a width of 65-90 mm. The thin wall block of stone MLK3 can be used in wall tiling, for example (Figure 5).
The deposit of Hopealoimu-stone (nodule mica schist of Pihtipudas) is reportedly the only site of its kind in the world. The rich mica content makes the surface of the stone glisten in the light. Due to its quartz content, the stone is highly resistant to wear: it does not become brittle in freezing temperatures, does not decompose in the industrial environment and does not contain rusting minerals. The main minerals of the stone are quartz stone (32%), biotite (33%) and feldspar (25%). The vividly glittering surface of the stone is given by the andalusite (3%) and cordierite occurring in scattered granules.