Does the Elemental Gem require Concentration?

Does an elemental summoned from an Elemental Gem require Concentration? I am getting hung up on the "as if you had cast" part. Other items say, "you can use an action to cast the [spell]".

Elemental Gem

This gem contains a mote of elemental energy. When you use an action to break the gem, an elemental is summoned as if you had cast the conjure elemental spell, and the gem’s magic is lost. The type of gem determines the elemental summoned by the spell.

Related question: Do magic item spells require concentration?

The distinction I’m asking then is if the Elemental Gem is a spell or a spell-like effect.