Final answer:
The described painting technique using thin transparent layers built up to create a deep, luminous quality is known as oil glazing, which was perfected by Flemish artists like Van Eyck during the Northern Renaissance.
Step-by-step explanation:
The question you're asking is related to the painting technique used by Flemish artists like Van Eyck, which is characterized by thin transparent layers of paint that are built up on the canvas to create a jewel-like quality and smooth surfaces. This technique is associated with oil painting, particularly with the method known as oil glazing.
Oil paint allows for a wide range of pigment options and the flexibility to be thinned into transparent glazes or used in thicker applications like impasto.
However, the focus here is the former, where multiple transparent layers, or glazes, are applied to achieve depth of color and luminosity.
Van Eyck and other Northern Renaissance artists mastered this technique to create paintings with remarkable detail and realistic effects, such as the illusion of light reflecting off surfaces and the depth of color in materials depicted, like metal or jewels.