Melt point, and what it decides

The number that separates a container wax from a pillar wax, and the one that decides whether your candles survive a warm delivery van.

Two temperatures on the data sheet

Melt point: where the wax becomes liquid.

Pour temperature: the range the supplier recommends filling at, which is lower and is about surface finish rather than about melting.

They are different numbers and people conflate them. Pouring at melt point gives you a rough top and wet spots.

Container wax and pillar wax

Container waxes have lower melt points and are formulated to cling to the vessel wall.

Pillar waxes are harder and formulated to release from a mold and stand up on their own.

Using one for the other fails in both directions: a container wax pillar slumps, and a pillar wax in a jar shrinks away from the glass and looks terrible.

What melt point decides

How the candle looks in the jar, through adhesion to the glass.

How readily it releases from a mold.

How much heat the wick has to deliver, and therefore the wick size.

And what happens in a warm room before it is ever lit.

Why a hot climate changes the answer

A wax with a melt point close to a warm summer interior will soften on a shelf, and a softened surface sets uneven.

A delivery vehicle in July goes well above any container wax's melt point. The candle arrives with a collapsed surface and, in a jar, often with the wick leaning.

Which is a shipping decision as much as a wax decision: either a harder blend for summer, or a dispatch policy that keeps candles out of the worst of it.

References