Silver

Silver is a dominant gene, where only one copy of the gene is required to express. Silver creates an effect in the base coat alone, and does not effect the color of the stripes at all. There are plenty of available ways to express silver dependent on other genes that are present, so we will break them down by associated genes to make it easier!

Some things to keep in mind about silver:

Silver will never affect the stripe color. As a result, it will never affect features that are directly linked to the agouti gene: In the case of charcoal tabby, the charcoal gradient will always be as dark as the stripe color even when silver is present. In the case of bengal tabby, the "inside" of the stripes will not be affected by silver.

Silver on solid cats

This section applies to all black-based solid cats (black, gray, chocolate, lilac, cinnamon, fawn, amber and mocha). On solid cats, silver creates a pattern commonly known as smoke. This pattern drastically lightens the following areas:

Chest
Belly

It can extend to, though usually at a lesser intensity, to:

Face
Body
Tail (halfway)

It never affects

Top of head
Ears
Legs
paws
End of tail

The absolute minimum for any smoke pattern in the import lineart.

minimum smoke - soft edged

smoke, with a blended edge

Silver / Smoke should always have soft or blurred edges. (minimum) Smoke should always be drastically lighter than the base coat, but the color can blend into the coat.

Minimum smoke - soft edged

Maximum smoke - soft edged

Minimum smoke - blurred

Maximum smoke - blurred

Silver on Tabbies

This section applies to all cats who express some form of tabby. In this expression, silver will lighten the base coat but leave the stripes in their original color. This means that the stripe color should always be within range for the non-silver color. Silver will affect the undercoat and tabby gradients, if present.

Silver will NOT affect gradients related to the tabby pattern themselves. If you're doing a gradient to replace ticking, the gradient should be stripe-colored. Similarly, charcoals should have the darkest part of their gradient match the stripe color.
Any gradients lightened by silver should be light enough so the cat still appears silver. If the cat appears non-silver, you'll be asked to lighten the base coat more.