Two grades, classified to spec.

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.

The range

Pick the grade your mix design needs.

Grade I Processed fly ash · lot-tested

NT Pozz — Grade I

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 2026
SiO₂ + Al₂O₃ + Fe₂O₃
93.08%
Fineness · Blaine
382 m²/kg
Loss on ignition
0.74%
Standard
IS 3812 Part 1 & 2

Lime reactivity and 28-day compressive strength were still under test when this report was issued — latest tested results available, remaining tests pending.

Quote Grade I →
Microfine Ultra-fine grade

NT Pozz — Microfine

An 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.
Mean particle size
3.9–5.0 µm
Surface area
~13,000 cm²/g
Loss on ignition
< 1.0%
Basis
Target spec, confirmed per lot
Enquire about Microfine →
Specification

Grade I — limit, result, lot.

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/kg382 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%not in this report0.04% SGS
Lime reactivity≥ 4.5 N/mm²Awaited—
Compressive strength — 28 day, % of control≥ 80%Awaited—

Latest tested results available — remaining tests pending. Lime reactivity and 28-day compressive strength were still under test when NBML-NN-1070-2026 was issued, so this lot is not presented as a completed pass against IS 3812; the figures are shared with the lot certificate once the laboratory releases them. 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. ASTM C618 Class F qualification is in progress: the SGS chemistry above is a partial cross-check, and the strength activity index and fineness work needed for a full Class F declaration is not complete. Ask us for the current position before you specify to C618.

Target specification

Microfine — target properties.

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.

ParameterTarget — subject to lot testing
Mean particle size3.9–5.0 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.

See the actual lab reports →
How we supply

From your enquiry to a load on site.

  1. 01

    Tell us the spec

    Grade, monthly tonnage and delivery location. WhatsApp, call or the enquiry form.

  2. 02

    We quote in 24 hr

    Availability, packing options and a landed price — with the test profile.

  3. 03

    We grade & certify

    Each consignment classified and lot-tested before it leaves the yard.

  4. 04

    Scheduled dispatch

    Loose bulk, container liner, 1 MT jumbo bag or 50 kg packing, planned against your pour schedule.

Loose bulk pneumatic discharge · dry bulk vessel Container liner sealed liner in a standard container Jumbo bags 1 MT FIBC, palletised · 50 kg bagged Multi-source lot-wise tested chemistry
National sourcing network

Classified at the silos, straight from the plant.

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.

Battery of fly ash storage silos at the source plant
Row of storage silos with material-handling gantry at the plant
Twin silos and conveyor structure at the fly ash facility

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.

Ready to price it?

Tell us the grade and tonnage.

Share your monthly volume and delivery location — we respond with availability, packing options and a landed price within one business day.

Get a quote → Where it goes
Get a quote