Brazilian and international buyers frequently receive offers of metallic lots in Brazil — ore, concentrate, tailings, artisanal mining bags, vein samples, mixed industrial maintenance lots. The offer profile is similar: a photo sent by message, a USD or BRL price, demand for an advance or immediate visit. The risk is also similar: the offer may be legitimate, partially legitimate, or fully fraudulent.
Local validation before commercial decision is what separates the three. This text explains what it covers, what it does not cover, and how to organise the request to save time on both sides.
What local validation covers
Field verification
On-site visit to the declared location, physical confirmation of the material's existence, geo-tagged photos, recording of operational context (warehouse, yard, deposit, mining site), basic identification of who delivered.
In offers where the lot photo is the only visual element, this already eliminates a class of situations: either the material is there at the declared volume, or it is not.
Visual technical inspection
Material physical form, granulometry, signs of mixing or contamination, packaging, presence of label or traceability. In many cases visual inspection alone shows whether the proposed sampling is representative or whether the lot is being misrepresented.
Preliminary XRF when matrix allows
For metallic concentrate or matrices where XRF gives a useful read, you get a preliminary number on site, before commissioning destructive assay. XRF does not replace fire assay but eliminates offers where the read is clearly inconsistent with declared values.
Sampling with chain of custody
Protocol-based collection, sealed and tracked transport to the partner laboratory. This is what separates a number that defends a commercial decision from a number that does not.
Confirmatory assay coordination
ICP-MS, ICP-OES or fire assay at a qualified laboratory, depending on matrix and buyer requirement. Report linked to the collected sample with cross-identification.
Basic documentary review
Seller identification, declared origin, declared operational context. Does not replace full legal due diligence.
Bilingual report
PT/EN, with photos, readings, assay where applicable and operational context. Several buyers use it as input for material they present internally.
What local validation does NOT cover
- Official mineral reserve certification. Reserves are certified by mining engineers and regulatory bodies (Brazilian ANM; JORC or NI 43-101 in formal projects). Preliminary field validation supports — does not replace.
- Full legal validation. Mining licence verification, tax compliance, corporate situation of the seller — remains with buyer's counsel.
- Refining. We do not refine; the report gives the buyer the technical basis to negotiate with the right recovery channel.
- Commercial guarantee. Validation reduces risk; does not eliminate. Commercial decision rests with the buyer.
Common red flags in Brazilian offers
Signals that demand caution before any advance:
- Disproportionate time pressure ("must close today, buyer arriving").
- Declared volume way above the typical scale of the operation the seller claims to have.
- Single photo, no contextual photo of the deposit, no identification photo, no scale weight.
- Request for advance to a third-party or foreign account before physical validation.
- Refusal to receive a visit or accept independent sampling.
- Message history with systematic technical identification errors.
- Documentation that looks copied from another lot (same photo, repeated angles, inconsistent metadata).
None of these alone proves fraud. The combination is what matters.
How to organise the validation request
- Forward the original offer. Photo, declared description, quantity, price asked, terms.
- Identify the seller. Name, company, declared location, contact, how the offer arrived.
- Define scope. Simple visit? Sampling? Sampling + assay? Full package? Each level has different cost and timeline.
- Agree on realistic timeline. Simple visit without long travel: a few business days. Sampling + lab assay: 1–3 weeks.
- Decide who pays. Some operations have the buyer paying for independent validation; others absorb the cost in the commercial deal; others split. We discuss before.
Cost vs. risk
Preliminary validation costs a fraction of what a lost advance on a fake offer costs. Costs an even smaller fraction of mobilising an international team for a lot that did not exist. The right question is not "is validation worth paying for" — it is "is closing without it worth it".
Technical page on due diligence →
For a specific offer, send the data via the submission form or WhatsApp. Reply with a technical plan and preliminary quote usually goes out the same business day.