One thing that sets these paintings apart is the use of 'Tibetan' gold. This is a pigment made entirely of powdered gold produced in a secret process by a group of highly skilled craftspeople in Nepal that has never been successfully recreated. A company in London produces a version of this paint, the quality and fineness of which is nowhere near that of the traditional gold paint from Kathmandu.
The gold paint is applied to many features both on the deity (eg. necklaces, earrings etc), to landscape features such as rock outcrops and trees, and to flame auras, thrones and lotuses among others. Some thangkas use extensive gold outlining (see thangka of Vajrayogini in the gallery) to almost every object in the composition, and there are also so-called 'gold' thangkas that are entirely gold with the figures 'drawn' on merely in outline form.
Each object in the painting is then outlined using dark colours such as indigo (used to outline blues and greens) and lac dye (a dark brownish red used to outline reds, oranges and yellows). Much of the skill of the painter can be measured in the fineness of the outlines he or she produces. It is this aspect that brings the painting alive with its use of varying line thicknesses to produce an illusion of movement, depth and character.
After burnishing the gold, painting in the eyes (always left until last) and inscribing the sacred letters and dedication of the back of the painting, it can be cut from the frame and mounted either in a traditional silk brocade or framed in a more western style frame depending on the wishes of the patron.