This is a diagram of the ear from Lanteri's 1902 Modelling book, with my own labels. Click on any image to enlarge it.
Most of the ear tutorials I have seen are very similar. Each person's ear is different, yet the same. The individual differences are in the details. My favorite place to look at photographic stock ear references is Deviant Art.
1. Start with a block ear form. The ear is tilted back about 15 degrees.
2. Use a tool to carve a groove to define the Helix.
3. Use a tool to carve out the Outer Auditory Canal.
4. Use a tool to carve out the Ear Notch, defining the Tragus, and Antitragus.
5. The Helix goes into the Outer Auditory Canal. There is a small V indentation at the top of the conch, making it look somewhat like a Y.
6. Smooth and blend all parts, using fingers, tools, brushes, and so forth.
Although I am done with this practice oil-clay ear, I keep noticing more things to do to it. In the turnaround photo below, I have moved the top of the ear away from the background (which would be the head, if this wasn't a practice ear), moved the ear lobe away from the background, and made the Outer Auditory Canal a little bigger. It is all in the details.
I am going to do a practice nose next.
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