Workability and water demand
Poorly graded fillers raise water demand and make mortars sticky or prone to bleeding. Mixes then lose strength, shrink more and are harder to apply consistently on site.
Industry · Construction
Construction Minerals for Mortar, Concrete and Geotechnical Works
Dolomite, calcium carbonate, bentonite and ball clay for dry-mix mortars, concrete, waterproofing and building products, supplied in bags or bulk jumbo bags.
ISO 9001 certified processes
NABL-accredited lab testing
CoA, TDS & MSDS with every shipment
Export packaging worldwide
Overview
Minerals engineered for construction
Construction minerals are high-volume inputs where consistency matters as much as price, because a single off-specification delivery can stop a dry-mix line. Obsidian Minerals supplies dolomite, calcium carbonate, bentonite and ball clay to producers of dry-mix mortar, concrete products, building boards, bricks and geotechnical materials.
Calcium carbonate and dolomite are the main fillers in tile adhesives, renders, plasters, putties and self-levelling compounds, where their particle size distribution controls packing, water demand and workability. Dolomite chips are used as aggregate in terrazzo, precast and decorative finishes. Sodium bentonite swells to many times its dry volume in water and forms a low-permeability barrier, which is why it is used in diaphragm wall, piling and tunnelling slurries, waterproofing membranes and landfill liners. Ball clay contributes plasticity and green strength to bricks, roof tiles and other heavy clay products.
Our construction range includes dolomite powder and chips, GCC grades, sodium and calcium bentonite, and standard ceramic ball clay. All products are tested in an NABL-accredited laboratory and shipped with a TDS and batch CoA, packed in 25 kg or 50 kg bags or 1 MT and 1.2 MT jumbo bags for silo and batching-plant handling. Samples are available for mix trials, and custom particle sizes can be developed with your technical team.
Problems we help solve
Waterproofing and seepage control
Basements, tunnels, landfill cells and retaining structures must resist water ingress. Barrier materials need high swelling and low permeability that remain effective under confining pressure.
Excavation stability
Diaphragm walls, bored piles and microtunnelling need a support fluid that holds the excavation open, suspends cuttings and forms a filter cake on the soil face.
Supply consistency at volume
Dry-mix plants run continuously on fixed recipes. Variations in filler fineness, moisture or whiteness disrupt dosing and product colour, so batch-to-batch consistency is essential for every delivery.
Recommended products for Construction
Dolomite
Dolomite Powder (200 / 325 Mesh)
Fine dolomite powder used as a filler in tile adhesives, putties, plasters and renders, helping to control particle packing, water demand and surface finish in dry-mix formulations.
View grade specs
Dolomite
Dolomite Chips (3–10 mm)
Dolomite chips in 3–10 mm sizes used as decorative and functional aggregate in terrazzo, precast panels, flooring and landscaping, offering a light colour and consistent grading.
View grade specs
Calcium Carbonate
GCC Standard Grade Calcium Carbonate
General-purpose ground calcium carbonate filler for wall putty, self-levelling compounds, renders and sealants, adding volume and a smooth finish at a controlled particle size and whiteness.
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Bentonite
Sodium Bentonite
High-swelling sodium bentonite for diaphragm wall and piling slurries, waterproofing membranes, slurry walls and landfill liners, forming low-permeability seals in contact with water and helping to hold excavations stable.
View grade specs
Ball Clay
Standard Ceramic Grade Ball Clay
Standard ceramic ball clay providing plasticity and green strength in bricks, roof tiles and heavy clay products, helping shaped units hold together through forming and drying.
View grade specsConstruction — common questions
Which fillers are used in tile adhesive and wall putty?
Ground calcium carbonate and dolomite powder are the most common mineral fillers in tile adhesives, wall putties, plasters and renders. They provide bulk, help control water demand and workability, and influence the smoothness of the finished surface. The grade and particle size distribution should be matched to the binder system and application thickness of each product.
How is bentonite used in piling and diaphragm walls?
Sodium bentonite is mixed with water to form a support slurry that fills the excavation as it is dug. The slurry exerts pressure on the trench or bore walls and forms a thin filter cake on the soil face, keeping the excavation stable until concrete displaces the slurry. Mixing and hydration should follow the project specification.
What sizes of dolomite chips do you supply?
Our standard dolomite chips are supplied in the 3–10 mm range, used for terrazzo, precast panels, flooring and landscaping. Other size fractions can be discussed on request to suit a specific mix design or finish. Samples are available so you can check colour, grading and appearance in your own product before ordering.
Can you supply construction minerals in bulk?
Yes. Construction minerals are packed in 25 kg or 50 kg HDPE or paper bags for site and plant use, or in 1 MT and 1.2 MT jumbo bags for silo filling and batching plants. Custom and private-label packaging is available on request, and every shipment includes a TDS, MSDS/SDS and batch Certificate of Analysis.
Request a quote
Talk to a construction specialist
Describe your process and current material. We will recommend a grade, share the datasheet and arrange samples for trial.