Mastic Mystery

Guys, my mother left the house. Unfortunately, she did not take her medication and If I don’t find her within the next hour, she may lay unconscious. She did not leave any message; I searched the whole house. A small chest, a present from her father, lies locked on a library shelf. A cupboard in the kitchen is also locked. I have asked her many times to tell me how they open because she may forget as time goes by. She always showed me the photo album and her diary and said “If you were really interested in our family and the production of mastic, you could easily open the padlocks”. Could you help me with this? If you can come up with something useful about where she might be, please call me right away on my cell phone!”