Source-linked AI summary
OreProof: Verifiable Provenance with Limited Disclosure for Critical-Minerals Supply Chains Using Zero-Knowledge Proofs
Oleksandr Hrabar, Hossein Arshadi Soufiani, Henry M. Kim, Chien-Chih Chen, Ali Vazirizadeh, Hjalmar Turesson
TL;DR
Critical-minerals supply chains need verifiable provenance but upstream actors resist exposing commercially sensitive data. OreProof prototypes a gold traceability platform using hybrid storage, zero-knowledge selective disclosure, batched anchoring, and standards-aligned credentials. Under the defined attacker model, directly inferable confidential attributes fell from three of four categories to none, while committed throughput was substantially higher than the baseline.
Problem
Upstream supply-chain data needed for independent provenance verification, including identities, grades, yields, and prices, is commercially sensitive and reluctant to be disclosed.
Method
OreProof combines off-chain confidential data with on-chain commitments, Groth16 proofs, Merkle-batched anchoring, and UNTP-aligned verifiable credentials in a gold use-case.
Results
Privacy leakage fell from 75% (3 of 4 categories) in the baseline to 0% (0 of 4 categories) in the privacy-preserving architecture, while committed throughput was 139 events per second versus 0.665 committed events per second.
Takeaways & Limitations
The prototype yields four nascent design principles for selective disclosure, conservative blended-commodity claims, standards-aligned credentials, and role-partitioned disclosure.
Takeaways & Limitations
The artifact runs on a public zkEVM testnet, and its privacy result measures direct leakage under a specific attacker model rather than absolute privacy.
Abstract
from arXiv · showhide
Critical-minerals supply chains face a structural tension: regulators and buyers demand verifiable provenance, yet upstream actors are hesitant to disclose supplier identities, assay grades/yields, and prices that verification appears to require. We report a design science account of OreProof, a prototypical traceability platform addressing this verifiability-disclosure trade-off. Instantiated for gold, OreProof combines a hybrid on-chain/off-chain data model, Groth16 zero-knowledge proofs for selective disclosure, a Merkle-batched anchoring pipeline, and UNTP-aligned verifiable credentials on a public zkEVM testnet. Against a transparent baseline, directly inferable confidential attributes fell from three of four categories to none under a defined attacker model, while batched anchoring substantially improved throughput. Our contributions are the artifact prototype as well as four nascent design principles: prove over committed data rather than exposing it; credential only verifiable origin and flag unknown inputs for blended commodities; emit standards-aligned credentials from the outset; and partition disclosure by supply-chain role.
1. Introduction
Critical-minerals traceability must satisfy rising provenance and passport requirements without forcing upstream actors to disclose commercially sensitive data. OreProof addresses this design problem through privacy-preserving proofs, hybrid data storage, batched anchoring, and standards-aligned credentials.
- Regulatory regimes increasingly require digital product passports containing provenance and due-diligence data for products such as batteries.
- Transparent ledgers expose supplier relationships, while coarse access-controlled ledgers can prevent independent verification.
- UNTP alignment is treated as an early design requirement because incompatible data formats and vocabularies create duplicate compliance costs and may foreclose market access.
- OreProof asks how critical-minerals traceability can produce independently verifiable provenance claims while protecting upstream confidentiality and aligning with passport standards.
- The gold use-case keeps confidential data off-chain, uses Groth16 proofs for claims such as approved origin or minimum purity, batches lifecycle events, and issues UNTP-aligned credentials.
- The prototype contributes an instantiated artifact, design principles for credentialing and selective disclosure, and a standards-gap analysis for minerals.
2. Literature Review
Prior work addresses blockchain traceability, privacy, digital product passports, and enterprise architectures separately, but the reviewed literature does not combine these capabilities for critical-minerals provenance. OreProof is positioned to address that combination gap.
- Blockchain traceability research spans food, pharmaceutical, and agricultural settings, while confidentiality-focused systems use techniques such as zero-knowledge proofs or unlinkability.
- Existing systems often advance only one or two required capabilities, such as privacy, provenance, or standards alignment, rather than combining them.
- Zero-knowledge proofs support predicate checks against commitments without revealing the underlying data, providing the cryptographic basis for selective disclosure.
- Digital product passport research links data-sharing willingness to privacy concerns, while another implementation supports selective disclosure under the ESPR using decentralized identifiers and verifiable credentials.
- Enterprise architectures commonly keep sensitive payloads off-chain and commit hashes or references on-chain, a pattern OreProof extends with commitment-based selective disclosure.
- The authors identify no peer-reviewed system uniting hybrid storage, a zk-rollup environment, zero-knowledge selective disclosure, and UNTP and EU DPP alignment for critical-minerals traceability.
3. Theoretical Framing: The Verifiability-Disclosure Trade-off
The paper frames traceability as a trade-off between verifiability and confidentiality: conventional disclosure moves one at the expense of the other. Zero-knowledge proofs over committed data are presented as a way to sustain verifiability while holding confidentiality fixed.
- Supply-chain information sharing can improve coordination while exposing participants to competitive harm, especially in extractive settings.
- Verifiability is the degree to which an independent party can confirm a claim, while confidentiality protects commercially sensitive attributes from unauthorized parties.
- Conventional designs treat verifiability and confidentiality as substitutes: more disclosure raises verifiability and lowers confidentiality, while less disclosure does the reverse.
- Zero-knowledge proofs can establish that a committed value satisfies a predicate without revealing the value, decoupling verifiability from confidentiality.
- OreProof instantiates this framing with approved-origin membership and minimum grade or purity predicates proved against on-chain commitments.
- The evaluation operationalizes confidentiality as privacy leakage, while verifiability is demonstrated only for the implemented predicates rather than measured as a general quantity.
4. System Design and Architecture
OreProof uses a hybrid architecture that keeps sensitive traceability data off-chain while anchoring commitments, proofs, and standards-aligned credentials on-chain. Groth16 proofs support selective verification, Merkle batching improves committed throughput, and the evaluation reports reduced direct leakage under a defined attacker model.
- Architecture: Confidential attributes remain off-chain under application control, while the blockchain records audit-oriented artifacts such as commitments, hashes, proofs, and references.The platform is instantiated for gold provenance and uses a permissioned hybrid on-chain/off-chain design.
- Lifecycle and anchoring: Lifecycle events are canonicalized, inserted into a Merkle batching pipeline, and anchored on-chain through roots with scope metadata.The lifecycle covers ore registration, custody transfer, transformation or refining, and certification or attestation.
- Selective disclosure: Groth16 proofs let owners demonstrate approved origin, minimum grade, or purity against commitments without revealing the underlying commercial values.Verifiers check each proof against the corresponding on-chain commitment, enabling minimum necessary disclosure.
- Evaluation and measurement: 139.2 events/s was the committed business-event throughput for 2,000 events anchored by four Merkle-root transactions, versus 0.665 committed transactions/s for the sequential baseline.The redesigned system trades per-event finality latency for higher aggregate committed throughput through batching.
- Privacy leakage: 75% baseline privacy leakage fell to 0% for directly inferable confidential categories under the defined benchmark attacker model.The baseline exposed three of four categories; the hybrid design exposed none, while residual risks outside the model remain excluded.
- Design rationale: The two gains arise from different mechanisms: zero-knowledge selective disclosure removes direct attribute leakage, while batched anchoring raises committed throughput.The result is a private-verifiability model combined with a higher-throughput traceability architecture, not faster zero-knowledge transactions.
6. Discussion
OreProof yields four nascent design principles for selective disclosure, conservative credentialing, standards alignment, and role-structured access in critical-minerals traceability. The discussion also identifies standards gaps and bounds practical claims about adoption, equity, and governance.
- Design principles: DP1 requires proving over committed data rather than exposing the underlying data.This principle is most directly supported by the privacy-leakage result.
- Design principles: DP2 recommends credentialing only verifiable origin and explicitly flagging unknown inputs in physically blended commodities.The system avoids averaging blended material into an unsupported single-origin claim.
- Design principles: DP3 calls for standards-aligned verifiable credentials from the outset, while DP4 partitions disclosure by supply-chain role.These principles make interoperability and minimum necessary disclosure properties of the artifact.
- Standards implications: Four mapping gaps concern mining-specific event types, bulk-material granularity, multi-party conformity assessment, and national regulatory identifiers.The authors present these as input to ongoing UNTP and EU DPP standardization rather than permanent shortcomings.
- Implications and boundaries: Hybrid storage and zero-knowledge selective disclosure can support shared traceability without surrendering trade secrets, including for SMEs and small-scale miners.The claimed adoption and cost effects remain unquantified without field deployment.
- Implications and boundaries: Selective disclosure may lower participation barriers and address sensitivity differences, but equity and fairness depend on governance choices the artifact does not guarantee.The paper treats governance as future work and notes that enterprise blockchains can reproduce centralized control.
7. Concluding Remarks
OreProof is a proof-of-concept hybrid, zk-enabled, UNTP-aligned gold traceability platform that addresses verifiability without exposing sensitive provenance data. Its conclusions are bounded by testnet deployment, a specific attacker model, committed-event throughput measurement, and unresolved formal attestation questions.
- Concluding remarks: OreProof lets actors prove provenance and conformity claims without exposing the sensitive data behind them.The platform is instantiated for gold and combines hybrid storage, zero-knowledge proofs, and standards-aligned credentials.
- Concluding remarks: Three of four confidential-attribute categories became none under the benchmark attacker model, while batched anchoring substantially increased committed throughput.The privacy gain is attributed to commitments and zero-knowledge selective disclosure; the throughput gain is attributed to batching rather than proofs.
- Concluding remarks: The claims are bounded because the artifact runs on a public zkEVM testnet, privacy is measured under a specific attacker model, throughput counts committed events, and formal LBMA-recognized attestation remains open.These boundaries limit interpretation of the prototype's privacy, performance, and certification results.