The leaves reached Birmingham through Alphonse Mingana, an Assyrian-born scholar who made three buying journeys to the Middle East in the 1920s funded by Edward Cadbury of the chocolate firm. Mingana bought in quantity, in Mosul, in Cairo and elsewhere, and what he assembled became the Mingana Collection: several thousand Middle Eastern manuscripts in Syriac, Arabic and other languages, some of them of the first importance and many of them, inevitably, catalogued at speed.
The two Quran leaves were among the latter. They had been bound together with leaves of a different seventh-century Quran, in a similar early hand, and were treated as one manuscript. They sat that way for about ninety years, in an open collection at a British university, fully accessible to anyone who asked. The identification came in the 2010s, from a doctoral student working systematically through the early Quranic material, who saw that the two sets of leaves were not written by the same hand.
That is the part of this story worth keeping. The find was not made in a desert or a sealed cave. It was made in a catalogue, by looking again at something that had already been looked at, and it is a reminder that a collection which has been held for a century is not thereby a collection that has been read.