A workhorse Grade I for ready-mix, PPC and block work, tested to IS 3812 Part 1 & Part 2 — and an ultra-fine Microfine grade for high-performance concrete, offered against a target specification and confirmed by lot testing before dispatch.
Dry-collected, classified siliceous fly ash for ready-mix and site concrete, PPC and block work. Processed so a high proportion sits in the fine fraction — a controlled, consistent product, lot to lot.
Latest tested lot — NBML-NN-1070-2026 · 04 Aug 2026An ultra-fine grade for high-performance, high-durability concrete — a domestic substitute for silica fume. Near-spherical micron particles fill voids, cut water demand and drive long-term strength.
Target / typical properties — subject to lot testing. Not results from the reports on this site.Three different things, kept in three different columns: what the standard demands, what the laboratory measured on the latest lot, and what earlier lots read. Every figure is reproduced from a signed report published on this site.
| Parameter | Applicable requirementIS 3812 Part 1 | Latest test resultNBML 1070 · 04 Aug 2026 | Previous tested lots |
|---|---|---|---|
| SiO₂ + Al₂O₃ + Fe₂O₃ — pozzolanic oxides | ≥ 70% | 93.08% | 94.72% SGS · C311 |
| Silica (SiO₂) | ≥ 35% | 51.08% | 59.20% SGS |
| Loss on ignition | ≤ 5.0% | 0.74% | 0.34% SGS |
| Sulphur trioxide (SO₃) | ≤ 3.0% | 1.83% | 0.061% SGS |
| Magnesium oxide (MgO) | ≤ 5.0% | 1.22% | — |
| Available alkalis | ≤ 1.5% | 0.98% | — |
| Fineness — Blaine air permeability | ≥ 320 m²/kg | 382 m²/kg | — |
| Retained on 45 µm sieve | ≤ 34% | 30.12% | 20.40% · 21.00% NBML 0978 |
| Soundness — autoclave expansion | ≤ 0.8% | 0.09% | — |
| Moisture content | ≤ 3.0% | 0.68% | 0.04% SGS |
| Lime reactivity — 10 day | ≥ 4.5 N/mm² | 5.3 N/mm² | — |
| Strength activity index — 7 day, % of control | ≥ 75% ASTM C311 | 83.25% | — |
| Strength activity index — 28 day, % of control | ≥ 80% | 87.33% | — |
| Water requirement — % of control | ≤ 105% ASTM C618 | 97.25% | — |
Every parameter in this table was tested on the latest lot and meets its requirement. Results are lot-specific, not a guarantee of future lots — a signed test certificate accompanies every tested lot. Requirement column follows IS 3812 (Part 1) for use as pozzolana in cement and (Part 2) for use as an admixture in concrete. On this lot every ASTM C618 Class F requirement is also met: 93.08% pozzolanic oxides against a 50% minimum, 0.74% loss on ignition against 6.0%, 1.83% SO₃ against 5.0%, 0.68% moisture against 3.0%, 30.12% retained on 45 µm against 34%, a 7-day strength activity index of 83.25% against 75%, and 97.25% water requirement against 105%. The C618 chemistry was determined by IS methods with an independent SGS cross-check to ASTM C311; ask us for a lot-specific position before you specify to C618.
Microfine is offered against a target specification, not a published lot report. The figures below are what we classify to and confirm by testing before dispatch — they are not results from the reports on this site.
| Parameter | Target — subject to lot testing |
|---|---|
| Mean particle size | 3.9–5.0 µm |
| Surface area | ~13,000 cm²/g |
| SiO₂ + Al₂O₃ + Fe₂O₃ | ~95% |
| Retained on 45 µm sieve | < 10% |
| Loss on ignition | < 1.0% |
| Moisture | < 0.5% |
Target values only. Tell us the properties your mix design needs and we will classify and test against them, and issue the report before the load moves.
Grade, monthly tonnage and delivery location. WhatsApp, call or the enquiry form.
Availability, packing options and a landed price — with the test profile.
Each consignment classified and lot-tested before it leaves the yard.
Loose bulk, container liner, 1 MT jumbo bag or 50 kg packing, planned against your pour schedule.
Korba · Seepat · Kanhia · Talcher. Drawn from dedicated silos at each source and tested lot by lot, so chemistry is proven per consignment rather than assumed from a single plant.
Dry-collected and drawn from dedicated storage silos across our sourcing network — classified and lot-tested before dispatch, with the signed test certificate naming the lot it belongs to.
Share your monthly volume and delivery location — we respond with availability, packing options and a landed price within one business day.
