Mammonic Transmission Engineering, deposit #1625 of the Crimson Hexagonal Archive (16 September 2026), treats money as a transmission device rather than as a description of value, and asks what meaning can be sent through it. It grants money's engineering achievement without qualification — a claim carried across distance, time, mutual ignorance and mutual distrust at a range no other artifact approaches — and then specifies the channel's passband and stopband from a single law. That law is stated as an invariance: where two units are substitutable under a monetary operation, a property is natively transmissible when it takes the same value for both, so the native monetary form preserves exactly those properties invariant under substitution among admissible units. The stopband then follows rather than being asserted. Nominal magnitude, ordering, divisibility and settlement capacity survive, because any two units of a denomination share them. The history of a particular unit does not, because substituting another changes that history and changes nothing the operation reads; nor does who bore the cost, because bearing is whose; nor the relation between parties, because relation is between whom. And money cannot natively carry a prohibition on combining its own magnitudes, since a unit that could not be added to another of its kind would not be that unit. The paper's summary of the mechanism is that money buys transmission range by dropping semantic state, relieving each receiving node of reopening the originating account — so that provenance indifference and settlement are one engineering decision rather than two complaints, and the compression profile simply is the transmission protocol, the discarded features being what make repeated transmission cheap. Its new claim is the law's second half: what money transmits means something only where a particular still holds it. Holding is defined at token grain as a surviving connection to a determinate non-monetary relation that can bind interpretation, which institutional liabilities and accounting relations satisfy, so that accumulation does not destroy reference but outsources it to ledgers and mandates — every large position being two channels in parallel, one of which is not money, with the failure mode that reference fails when the ledger does while the money survives intact and unheld. Reference is thereby placed upstream of operative standing in a stack running reference, standing, price formation, write-back. The paper withdraws an earlier claim that the money-form requires an unbranded centre, as historically false, and replaces it with a stress test of particularization in which a personal mark enters currency through the authentication channel rather than as a relation to any transaction. Related: #642, #610, #1270, #1622, #311.