Consider this Part 2 from What happens to objects, changed while transmuted using Minor Alchemy, after they revert?

This is regarding the School of Transmutation wizard's Minor Alchemy feature (PHB, p. 119):

Starting at 2nd level when you select this school, you can temporarily alter the physical properties of one nonmagical object, changing it from one substance into another. You perform a special alchemical procedure on one object composed entirely of wood, stone (but not a gemstone), iron, copper, or silver, transforming it into a different one of those materials. For each 10 minutes you spend performing the procedure, you can transform up to 1 cubic foot of material. After 1 hour, or until you lose your concentration (as if you were concentrating on a spell), the material reverts to its original substance.

Specifically, with spells like Mold Earth (can manipulate stone/earth, changes last 1 hour), or Meld Into Stone (put body and belongings into stasis within a "coffin" of stone), what happens when the stone that you're working with was transmuted from wood and reverts back?

In addition, Fabricate states that the quality of the finished product depends on the material used, but does transmuting cheap wood to silver mean that I end up with a high quality silver product followed by it reverting to a high-quality wood product?

I guess, to simplify this question, assuming I'm converting wood into stone via Minor Alchemy: When I cast a spell that requires stone, does my spell:

  • Fail immediately (as I'm not using a proper material)
    • If this is true (I can't turn wood to stone, because it's not real stone), could I turn stone to wood and treat it as a stone material?
  • Fail the moment Minor Alchemy ceases (as I'm no longer using stone)
  • Continue to attempt the magic on the reverted material as normal (like with Mold Earth, magically ending up with colored, shape-shifted wood for the next hour)
  • Some other event

3 Answers 3


The answer is going to depend on whether the spell is still in effect when the reversion happens.


Fabricate is instantaneous. You cast the spell, the magic shapes the material, and then it holds that shape forever just as if you'd cast it or carved it.

The result of transmuting some cheap wood to fine silver, then Fabricating it into high-quality jewelry, then having it revert back, is that you now have fine jewelry made out of cheap wood. The delicate shapes are not going to hold up to wear. It's going to have the grain structure of the wood, which may be too coarse to show the details you want. It may have material flaws like knots and pockets of sap.

Fabricate has the limitation that making high-quality goods requires crafting proficiency appropriate to the thing you're making. I'd say that in this case, if you're proficient with both jeweler's and woodworker's tools, and knew that the silver was going to revert to wood, you could end up with high-quality woodcrafts. Otherwise you're going to get junk.

Meld Into Stone

This has a duration of 8 hours. It also addresses this issue:

Minor physical damage to the stone doesn't harm you, but its partial destruction or a change in its shape (to the extent that you no longer fit within it) expels you and deals 6d6 bludgeoning damage to you. The stone's complete destruction (or transmutation into a different substance) expels you and deals 50 bludgeoning damage to you.

So, good luck with that.

Mold Earth is instantaneous--kind of, sometimes.

The basic use of Mold Earth is like a magical shovel: it takes a chunk of dirt or stone and moves it.

But it also has those persistent effects that last 1 hour. My initial reading was that the spell reshapes the soil to achieve those effects, instantaneously, and then they disintegrate after an hour as the soil returns to its natural state, like a sandcastle. But you can dismiss the effect, which implies that the magic is still doing something. I could see a DM ruling either way on this.


Spells and abilities do exactly what they say.

As long as the conditions of the spell are meet the spell, spells work the way they say.

Meld into Stone already tells you what happens, as Mark Wells pointed out:

The stone's complete destruction (or transmutation into a different substance) expels you and deals 50 bludgeoning damage to you.

Invalid Target

When the target of a spell becomes invalid, there are no rules that apply, and the effect is up to the DM. Jeremy Crawford said as much here:

There's no rule governing what happens when a valid spell target temporarily becomes an invalid target. A good rule of thumb is that the spell is suppressed while the target is invalid.

I think his rule of thumb is a great way to handle all these edge cases. Take, mold earth, for instance. As long as it is Earth you can mold it, if it turns into an invalid target you can no longer mold it, as the effect is suppressed. If it turns back into Earth while you're still concentrating on the spell, you may mold it some more. Though this isn't a rules answer just advice from the game designer.

  • \$\begingroup\$ "If it turns back into Earth while you're still concentrating on the spell, you may mold it some more. " Mold Earth is problematic because it doesn't require concentration, or even strictly have a duration. It just has an effect that lasts one hour or until dismissed by the caster. How this is different from a one-hour duration beats the heck out of me. \$\endgroup\$
    – Mark Wells
    Sep 29, 2018 at 0:09

Fail the moment Minor Alchemy ceases

For context, I think it's important to compare the behavior of spells cast using Minor Alchemy-transmuted components vs other ways that magically altered components interact with spells. For example, the 5th level spell Creation, which has a special clause for when you use the materials summoned by this spell as a component:

Using any material created by this spell as another spell's material component causes that spell to fail.

Contrast with Minor Alchemy, which makes no mention of any such limitation. By this logic, I'm left to presume that so long as the matter in question remains of the type that the spell calls for, it's perfectly valid for use.

So, if the spell requires some quantity of stone, either as a component, or for the behavior of the spell, then it remains valid for the spell so long as it remains of that type.

A few obvious caveats

Minor Alchemy demands that the wizard maintain concentration on the effect, like concentrating on a spell. This means that any other effect that requires concentration and depends on the behavior of this material will probably not function (unless cast by an entirely different spellcaster).

Additionally, some spells have instantaneous durations. I think we can presume in this situation, much like your previous question, that the outcome of such spells remains in place regardless of the transmutation reverting. Burned wood would turn to stone dust, smelted iron would turn into lava, or into molten wood soaklogsinwood, or whatever.

Also bear in mind that Minor Alchemy places an explicit restriction on the use of gemstones, either as a transmutation source or target. This is almost certainly to prevent spellcasting cost exploits.

  • \$\begingroup\$ Also these instances, the object transmuted isn't the spell components, but the target of the spell. Fabricate is Verbal Somatic only, no material components. So creation+fabricate would technically work. \$\endgroup\$ Sep 28, 2018 at 19:06

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