Gold — Bambouk, the Falémé valley. Its value: the metal.

Long before the year 1000, gold panned from the rivers of eastern Senegal crossed the Sahara by caravan. It made Ghana rich, then Mali.

1324 — Mansa Musa in Cairo. Its value: scarcity.

On his way to Mecca, the emperor of Mali spent so much gold in Cairo that its price there fell for about twelve years — or so al-Umari wrote. Too much gold, and gold is worth less.

Cowries — Markets of Mali, 14th century. Its value: everyone agrees.

For everyday trade, people counted in shells from the Indian Ocean. Worthless in themselves, accepted by the whole market. Ibn Battuta noted a rate: 1,150 cowries to one gold dinar.

1945 — The CFA franc is born. Its value: an issuer.

On 26 December 1945 the CFA franc was created. Money became state coins and banknotes, its value guaranteed by the issuer.

Cash — Decades of banknotes. Its limit: the paper trail.

Money had to be counted, carried and kept. It got lost, it got stolen, and when it changed hands only a receipt proved it.

Mobile — Wave, Orange Money. Its limit: separate books.

Today people pay with their phones. But Wave on one side, Orange Money on the other: for a merchant that’s two accounts, two statements, two ways to check.

Xaalis — Dakar, today. Its value: proof.

One ledger for all your payments: every franc written on both sides, every notification signed, nothing counted twice. Money without weight is worth what its books are worth.

Tomorrow — From Dakar across West Africa. Our ambition.

The CFA franc is already shared by eight West African countries. From Dakar, we’re building the infrastructure for money to move between their phones with the same proof — then across the continent.