The Step by Step
The Fundamental Tools:
• Having a graphite pencil with soft lead (6B for example) at hand will allow you to easily reach higher tones.
• A paper diffuser will help to integrate the tones in the points that require greater definition in the drawing (edges, corners, abrupt transitions of tone).
• A soft brush or the use of a cotton speck will facilitate the integration and blur the lighter tones, giving the uniformity required to represent a continuous and translucent face like that of glass.
The Trick: "The darkest tone"
The crystals, despite their level of transparency, generate very dark internal spaces, which depends on the angle at which the light strikes and the intensity of the light, as well as on the direction in which the object can be observed, since these they have the peculiarity of allowing the passage of light through the walls of the same but they create a dark environment in the transverse direction of these walls. Representing this darkness in the drawing will provide an excellent added value in order to achieve a result with realistic appearance.
This was the result obtained!!