Chlorophyte Ore

The ore starts forming as soon as a world goes hardmode, but nothing in your bag will scratch it yet. The first tool with enough power behind it is the Pickaxe Axe or the Drax, and both of those want bars from all three mechanical bosses. Explosives do not work either. The green glow you find while chasing a mech fight is a preview rather than a resource, and there is no shortcut around that gate.

It only appears where mud sits near jungle grass, and only from the lower half of the underground layer downward. The surface jungle produces none of it no matter how long you wait. Each patch of jungle grass down there periodically tries to convert a mud block within a few tiles of itself, and the attempt fails if a tree, a Life Fruit or a Plantera bulb is sitting directly above the target. That last rule is why the densest jungle ceilings often look barren.

The deposit is alive. Left alone it converts adjacent mud and jungle grass into more of itself, so the correct way to harvest is to strip most of a vein and deliberately leave a few tiles behind as seed. Come back later and the patch has refilled. Clear one to nothing and you go find another.

Spread stops once there is already a lot of ore around, and that check runs at two different radii, one tight and one wide. It is why a single blob never keeps doubling on itself. Seed tiles scattered thinly along a long stretch of mud produce far more per hour than one fat pocket. Chlorophyte Bricks spread the ore exactly the same way, so converting part of your haul into brick and laying it out in a line covers much more ground than the raw ore could.

The ore builds its own conditions. It turns nearby dirt into mud, and it converts corrupt, crimson, hallowed and ordinary grass into jungle grass, so a mud platform anywhere below the halfway line of the underground will eventually behave like jungle. Dirt is fully renewable through Dirt Bombs, and stone and wood can be shimmered into more of it, which makes the whole supply chain self sustaining.

Two limits to plan around. Mushroom grass is immune, so a glowing mushroom biome will never host a farm. And the ore inherits whatever state it takes over, coming out hammered, actuated or painted if the block it replaced was, which is worth knowing before you build a tidy farm out of shaped blocks.

A Spelunker Potion lights it up like any other ore and is by far the fastest way to locate wild veins. The green shine on exposed deposits is cosmetic: whatever the tooltip implies, it grows perfectly well in the dark.

It also holds back corruption and crimson creeping in around it, so a line of ore or brick doubles as a quarantine wall. Late in a run, shimmering Luminite is a much faster source than mining at all. And if you are selling rather than crafting, refine it into Chlorophyte Bars first, since the bar is worth more than the ore that went into it.

It is chlorophyll with the standard mineral ending stapled on. Broken apart, the prefix means green and the suffix means plant, so the word translates to roughly green plant. Chlorophyta is also a real division of green algae, which fits an ore that behaves like something growing.