Instead of a longer article, I went for one article per structure.
Here are the others:

• Hoof Wall
• Sole
• Frog & Collateral Grooves
• White Line
• Bars
• Heels & Heel Bulbs

Coronary Band / Groove

It’s the hoof’s crone, link between hard wall and soft skin and hair. It should be firm, straight and relaxed, and it should be where the coffin bone and P2 meet.

It is highly vascularised and produces wall tubules. It also adds more flexibility and absorbs some of the distortions the hoof has during the stride.

Here are healthy coronary band and periople skin.
The coronary band can give indications on what’s happening in the foot. Here is a front foot of a chronically foundered draft. The blue line outlines the actual coronary band and the green line, where the coronary band should be.
The coronary band is being pulled down at the toe by P3, as the bone sinks in the foot.

Periople skin

It is a thin layer of skin growing from the coronary band down to a 1/4 to 1/3 of the hoof wall.

During dry weather periods, it just looks like dry skin. During wetter periods though, it looks mushier, jelly-like, like when you spend too much time in water and you fingers start looking like great-grand-ma’s fingers! So, that’s normal if it changes aspect when the weather changes 😉

The wall grows from the coronary band down to the toe and the newly grown wall is naturally suppler than older wall to protect even more the coronary band and internal structures from shocks and vibrations. The periople skin’s role is to protect this softer baby wall.

In this photo, the periople skin is pushed up the coronary band because of the mud, and lifts the hair. Nothing is wrong here, it’s just a change due to the environment.