A fractional-gold app lets someone buy a tenth of a gram. Almost every one of them is a dealer: the operator quotes a price, takes the other side, and carries the inventory. Turning it into an auction market makes existing holders into supply, publishes one price with the volume behind it, and gets the operator out of the middle of every trade.
Most fractional-gold products are principal dealing wearing a market’s clothes. The screen shows a price and a chart, but there is no book behind it — the operator is the counterparty to every buy and every sell, and the number on the screen is a reference feed plus a margin.
Each customer buy is a principal trade against the app’s own inventory. The spread is the revenue, and the operator carries price risk between the customer’s tap and its own hedge — which is why the spread has to be wide enough to survive a bad minute.
A wholesale feed price, plus a markup, minus a markdown. Nothing in that mechanism lets a customer who is willing to sell at less improve the price another customer pays. Two customers on opposite sides of the same trade never meet; they both pay the operator.
A 0.2 g order is a rounding error against the smallest lot any wholesale counterparty will quote. So the operator warehouses retail flow, nets it internally by hand or by batch job, and hedges the residual — a position management problem that grows with the customer base.
Customer balances live in application tables. Reconciling them against the vault’s holdings is a periodic exercise run by a script, and when the two disagree the question of which one is right is answered by argument rather than by replay.
An order book changes who is on the other side. The operator stops being the counterparty and becomes the venue: it runs the market, publishes the price, and takes a fee per trade instead of a spread per position.
A customer who wants out is not a redemption request against the operator’s balance sheet; they are an offer in the book. Retail buying and retail selling clear against each other, and the operator only has to source the imbalance rather than the whole flow.
Price–time priority produces a single best bid and best offer that everyone sees, and every print carries a quantity. Instead of “our price today”, the customer sees the price at which the last trade actually happened and the depth on either side of it.
Order quantity in the engine is an integer count of lots. Set the lot to 0.01 g and 0.2 g is simply 20 lots — the same arithmetic the engine does for a thousand shares. The tick table keeps prices on a grid so that two orders at “the same price” really are.
A call auction collects orders without executing, disseminates an Indicative Equilibrium Price while it fills up, and uncrosses at the price that trades the greatest volume. That price is a much better daily reference than a feed snapshot, because your own market produced it.
An iceberg order displays a small peak and keeps the rest hidden, but contributes its whole volume to auction price discovery. A market maker can back the retail book with real depth without advertising exactly how much metal is behind it.
The market mechanics, the pre-trade controls and the post-trade record. One instrument, one currency, one commodity — this is the smallest configuration Mehrex runs, and the one that goes live fastest.
| Setting | Typical starting point |
|---|---|
| Instrument | One: gold of a stated fineness, in one currency |
| Lot size | 0.01 g — order quantity is an integer count of lots |
| Tick | Currency per lot, on a tick table that widens with price |
| Sessions | Opening auction, continuous trading, closing auction |
| Price band | A tolerance around the reference price; breaches halt rather than print |
| Accounts | Client account per end investor; house account for the market maker |
| Settlement | Pre-funded cash and pre-deposited metal, netted per cycle |
Price–time priority in 0.01 g lots, an opening auction with a live Indicative Equilibrium Price, and iceberg orders so a supplier can back the book without showing its hand.
Read more →04 · coreBuying power evaluated before the order reaches the book, per end investor. A customer cannot buy gold against money they have not deposited, and the rejection names the limit that stopped them.
Read more →05 · post-tradeEvery fill stamped with its clearing type, netted per participant and settlement date, with fees computed per trade — so the app’s ledger is fed by the venue rather than reconstructed from it.
Read more →06 · channelThe consumer app talks to the HTTP/JSON trading API and consumes snapshot-then-stream market data, so the book on a phone is the book in the engine rather than a poll of a cache.
Read more →Mehrex matches orders and records what happened. It does not hold metal, move money, or make you legal. On a retail gold product, the things it does not do are the majority of the build.
Somebody has to hold the bars, insure them, and be audited on them. The distinction between allocated metal a customer owns outright and an unallocated claim against a pool is a legal one with a very different outcome in an insolvency, and it is settled in your vault contracts — not in the engine. Mehrex moves entitlements between accounts; it has no opinion about what backs them.
Card acquiring or bank transfer in, payouts out, client-money segregation, refunds, chargebacks and the fraud that comes with all of it. Pre-trade risk checks buying power against a balance you maintain; keeping that balance truthful against your payment provider is your system’s job.
Onboarding identity checks, ongoing screening, transaction monitoring and suspicious-activity reporting. Precious metals attract specific attention in most AML regimes. The engine enforces that an order belongs to a registered, active client of a known member; deciding who is allowed to be that client is upstream of it.
Retail precious-metal products are regulated inconsistently. Some jurisdictions treat a fractional-gold entitlement as a commodity sale, some as a collective investment, some as a derivative the moment it is not physically deliverable on demand. Get that answered before you build, because the answer changes the product, not just the paperwork.
Mehrex ships a Client Trading Front-End, and it is a trader’s tool — a book, a ladder, an order pad. It is the right screen for your market-making desk and your operations team, and the wrong one for a retail customer. Onboarding, wallet, statements, tax reporting and the buy button are yours to build against the API.
A book with only retail orders in it is thin, wide, and disappointing on the day it matters. You need a market maker — very possibly still you, but now in a defined role with a house account, quoting obligations and its own risk profile, rather than as the invisible counterparty to everything.
The moment a customer can ask for a one-ounce bar, you have a fulfilment operation: minimum sizes, fabrication, shipping, insurance and the tax treatment of a physical delivery. It is a good feature and it is entirely outside the trading system.
Yes. Order quantity in Mehrex is an integer count of a configurable lot, so the lot is set to the smallest unit the market should trade — 0.01 g, for instance — and a 0.2 g order is 20 lots. The engine does integer arithmetic throughout; there is no floating-point quantity to round.
No. Mehrex is a matching, risk and clearing engine. It maintains positions and entitlements in accounts and records what was traded; the metal sits in a vault under a custody arrangement you make, and reconciling the two is your system’s responsibility.
A pre-trade buying-power limit evaluated at end-investor level before the order reaches the book. Limits are also evaluated at trading-member and clearing-member level, and an order is accepted only if every applicable level passes. Rejections name the limit and the scope that tripped.
The venue configuration is small — one instrument, one currency, one session pattern — and is settled in a market-model workshop and configured in the Control Panel. The schedule is usually set by custody, payment rails and licensing rather than by the engine.
Energy-saving certificates, RECs, guarantees of origin and carbon credits — instruments defined by paper, priced today by survey.
Read the page →Commodities & industrialsSilver, zinc and copper in physical lots — brokered by telephone today, at differentials nobody publishes.
Read the page →Commodities & industrialsGrain, coffee, cocoa and pulses traded as graded, warehouse-receipted lots on a frontier-market exchange.
Read the page →A live demonstration runs about an hour: the order book, the Control Panel, an auction uncrossing, and a replay of the journal that produced it.