How the Programme Works
The Dubai Jewellery Monthly Gift Card Reward Programme rewards our members with a transparent, fair, and cryptographically verifiable system, while offering exquisite jewellery rewards.
1. Programme Overview & Mechanics
- Monthly purchase: Members purchase a Dubai Jewellery digital gift card of CHF 100 per monthly cycle.
- Ticket issuance: After each successful monthly purchase, one digital reward ticket is automatically issued and recorded on the member’s account once payment is completed.
- Monthly draw & reveal: On the reveal date — the 25th of each month — all eligible tickets participate in the draw. One winning ticket is selected through our transparent, verifiable draw system.
- Checking results: On reveal day, eligible members log in to their dashboard and reveal the winning number through the interactive digital scratch card.
What jewellery can be claimed
Reward credits are credited directly to the winner’s customer account and can be redeemed towards eligible jewellery purchases from Dubai Jewellery GmbH, including 22K and 18K gold jewellery, diamond and wedding jewellery, necklaces, rings, bangles, bracelets, earrings, pendants, custom orders, and gold coins.
Strict exclusions & limitations
- No cash redemptions: Rewards, gift card balances, promotional credits, and winnings cannot be exchanged for cash, transferred to a bank account, or redeemed for precious metal investment products (e.g., gold bars).
- Usage restrictions: Reward credits cannot be applied to cash withdrawals or existing deposits, and cannot be combined with other promotional programmes unless explicitly stated.
- Participation cap: Each customer may participate only once per monthly cycle. A maximum of one eligible reward ticket is issued per customer per month.
2. Cryptographic Draw Verification
Our draw system is engineered to be transparent, fair, tamper-resistant, and completely independently verifiable. No employee, manager, or system administrator can alter or manipulate the outcome after the draw has been committed. The process follows a strict Commit-and-Reveal cryptographic design.
Step 1 — Commit
Before the draw, the system generates a secret random value called a Seed. The seed stays secret; the system publishes only its SHA-256 fingerprint — e.g. SHA-256(seed) = 9f8a7c4e8d1b…. This proves the seed existed beforehand while ensuring nobody can reverse-engineer it.
Step 2 — Reveal
On draw day, the original seed is revealed. At the same moment the participant list is frozen, ticket numbers are locked, a public random value is collected, and the winning ticket is calculated automatically.
Step 3 — Verify
Any participant can independently audit the result: hash the revealed seed, confirm it matches the pre-published fingerprint, and run the public formula. If any variable differs, the draw is instantly flagged as invalid.
3. Winner Selection Formula
The winner is governed entirely by mathematics, free from human intervention. Once the inputs are published, the winning ticket index is resolved as:
| Input | Meaning & function in the draw |
|---|---|
| seed | Secret value generated and committed before the draw takes place. |
| publicRandom | A public random value available to everyone, adding real-time entropy. |
| schemeId | The unique identifier for the specific reward programme. |
| period | The specific month cycle being drawn. |
| sortedTickets | The complete, locked, timestamped list of all valid tickets in that cycle. |
| N | The total number of valid tickets issued for the month. |
All inputs are combined into a single string; SHA-256 converts it into a unique 256-bit hash; the hash is divided by the total number of tickets (N); the remainder (mod N) determines the winning ticket number. Example: if the hash result is 450 and there are 100 tickets, then 450 mod 100 = 50 → winning ticket #50. The resulting index points directly to one ticket in the sorted list — no human chooses the winner.
4. Why It Is Secure
SHA-256 converts any information into a unique 256-bit fingerprint. It is one of the world’s most trusted cryptographic algorithms, used by Google, Microsoft, Amazon, Bitcoin, and international banking networks. Its search space is roughly 1.15 × 10⁷⁷ combinations — vastly more than the grains of sand on Earth — rendering brute-force attacks infeasible.
| Potential attack | Feasible? | Mitigation |
|---|---|---|
| Guessing the winner before the draw | No | Practically impossible due to the one-way nature of SHA-256. |
| Changing the seed after publication | No | Instantly detectable; changing one character alters the hash completely. |
| Manipulating or adding tickets post-draw | No | Detected immediately — the frozen list changes the final hash. |
| Forcing a predetermined winner | No | Prevented by combining the secret seed with the real-time public random value. |
| Faking verification results | No | The verification parameters are public and immutable. |
| Independent public recalculation | Yes | Fully supported — anyone can download the data and audit the draw. |
5. Transparency Timeline
To maintain the highest levels of transparency, Dubai Jewellery follows a strict protocol for publishing data each cycle:
- 7 days before the draw: publish the SHA-256 fingerprint of the committed seed.
- 24 hours before the draw: freeze and publish the sorted ticket list.
- Draw day (25th): reveal the original secret seed and the public random value, opening the system for validation.
- Continuous access: a dedicated Verify a draw page lets anyone perform automated or manual verification at any time.
With this provably-fair framework, the programme achieves a standard of security and trust comparable to modern blockchain applications, while keeping a clear, user-friendly experience for members.
Verify any past draw yourself — open the Verify a draw tool and recompute the winner from the public record.