You’ll notice that the wax is yellow-orange; probably it is unbleached beeswax. Normally we use unbleached candles for funerals and penitential seasons. However, it could be that they leave it unbleached for the Easter candle to emphasize the fact that it is beeswax – “the work of bees”, as the Exsultet so beautifully says:
On this, your night of grace, O holy Father, accept this candle, a solemn offering, the work of bees and of your servants’ hands, an evening sacrifice of praise, this gift from your most holy Church. […]
But now we know the praises of this pillar, which glowing fire ignites for God’s honor, a fire into many flames divided, yet never dimmed by sharing of its light, for it is fed by melting wax, drawn out by mother bees to build a torch so precious.
In medieval southern Italy (especially, but not only there), it was a custom to sing the Exsultet at the Easter vigil from an illuminated scroll. Here is a famous section of one of those scrolls, showing the bees that produced the wax for the candle:
New Liturgical Movement has a great post about the bees (and another painted paschal candle) here at this link.