This study describes the examination and analysis of four mixed media paintings from the 1960s and 1970s by Canadian artist Jack Chambers (1931–1978). The documentary evidence about his materials and methods is summarized and compared with the results of analysis of multilayer paint samples. The combination of Fourier transform infrared spectroscopy (FTIR) and gas chromatography-mass spectrometry (GC-MS) allowed the components of the paint media to be characterized: ortho-phthalate alkyd resins, iso-phthalate alkyd resins, drying oils, dammar, Pinaceae resin, and turpentine were identified in varying proportions. Many pigments and fillers were identified by FTIR and Raman and are enumerated. The effect that Chambers’ complex technique has had on the aging and degradation of the paintings is discussed. The severe cracking of the paint layers in one of the four paintings may be the result of a high proportion of dammar and turpentine diluent mixed with the alkyd paint and may also be related to the type of alkyd resin medium. Different history and environmental conditions may also be factors.