Work began on clearing and sifting through the rubble according to archaeological principles on 4th January 1993 with the intention of using as many original stones as possible to rebuild the Frauenkirche. The mound of rubble was initially divided into grid squares to allow a better orientation and to document the actual condition. Each find was marked and numbered before being carefully taken away. All data such as dimensions, finding place, a brief description of the find with a sketch and neighbouring finds were subsequently used for preliminary identification. The digital records of the finds were evaluated by photogrammetry to enable later revision and correction.

The 22,000 m³ mound of rubble was cleared in only 17 months. 8,390 façade stones and interior wall and ceiling stones as well as 91,500 back-up blocks could be saved. A lot of other objects were documented in addition to the stone finds. It was certainly a very happy day when the pinnacle cross and its boss were unexpectedly found on 1st June 1993, even though they were greatly damaged.