Raman has long been established as a nondestructive and noninvasive technique that has found increasing application in the area of cultural heritage and the study of works of art. Here, we present a further application of Raman spectroscopy in the study of an oil painting belonging to the de Brécy Trust. In the work presented, Raman microscopy has been employed to spectroscopically study minute fragments of excised pigments from a small oil painting bearing the hallmarks of a study sketch by the famous English landscape artist John Constable. Raman spectra were collected from 18 discrete areas of the work, chosen due to their colour in order to potentially cover all of the pigments used in this work. Of the 18, six positive identifications were made, confirming that the painting contained pigments and minerals known to be favoured by the artist. Whilst the remaining 12 sample sites were complicated by the fluorescence effects observed from the applied varnish, this can be useful in providing evidence to support the application of the ‘scumbling’ technique known to be favoured by Constable. We have positively identified the pigments: ultramarine/lapis lazuli, lead white, red lead, Prussian blue, chrome yellow and ivory black. We have also identified amorphous carbon and gypsum. These positively identified pigments link into Constable's existing colour box and four palettes, providing evidence that could lead to the painting being attributed to Constable. Excised fragments of paint and varnish from a purported John Constable painting have been examined using Raman spectroscopy in order to identify the pigments used and their relation to John Constable's colour palette. This work identifies some of the pigments used in this painting and confirms their link to Constable's palette. Further evidence of degraded varnish provides evidence of a technique called scumbling, a technique used in Constable's early career. This work demonstrates the powerful ability of Raman to offer key evidence for the provenance of artworks.