Figure 3 . The excavation drawings of the west profile , and level six and seven . The red dots mark the find spot of the mask ( upper left : west profile ; upper right : level seven ; below : level six ). One square is equal to 20 centimetres ( After Erfgoed Leiden en Omstreken ).
all these potentially reusable metal finds would have been discarded or lost .
Description of the Matilo mask The Matilo mask is made of bronze that was hammered and chased into a face with a Hellenistic masculine expression and hairdo ( Hazenberg 1997 , 38-39 ). There are holes on the sides of the face beneath the slightly protruding ears , in the eyes , mouth and nose ( fig . 2 ). A hinge is located in the middle of the helmet .
The morphological features of the face and hairdo of the mask point towards the Alexander type and only a few of these masks have been found ( Hazenberg 1997 , 38-39 ). Using Robinson ’ s typology the mask can be characterized as a type D parade helmet , which dates to the first and second century CE ( Robinson 1975 , 118 ).
Lastly , the hinge of the mask was broken ( fig . 2 ), indicating that the mask was broken from its helmet , but it is unclear if this happened before
or after deposition .
Build-up of the Corbulo channel at the findlocation The find spot of the mask in the Corbulo channel is situated between the vicus and castellum , near a revetment and a bridge ( fig . 1 ). The mask was found in the lowest and oldest fill of the channel ( in trench three of the 1996 excavation ), which was interpreted as ‘ stirred ’ soil ( fig . 3 ; Van Enckevort and Hazenberg 1997 , 38 ). Based on the ceramic and metal finds the mask layer can be dated between 75 and 150 CE , coinciding with the previously mentioned date of the mask ( De Rijk 2015 , 41 ). This mask layer constituted level six and seven in the excavation ( fig . 3 ). It is possible that the mask ended up there as a result of erosion , before the dump layer that