|This article is about an older version of DF.|
|This feature has one or more outstanding bugs.|
Magma-safe materials are materials which will not melt, burn, evaporate, or otherwise take damage when in close contact with magma. Most frequently, this comes into play when using floodgates operated by mechanisms.
For reactions and custom buildings using the [MAGMA_BUILD_SAFE] token, only a material which is solid and stable at the temperature (i.e. MELTING_POINT/BOILING_POINT/IGNITE_POINT/HEATDAM_POINT greater than 12000 and COLDDAM_POINT less than 12000) is supposed to be considered magma-safe; due to a bug, however, the game only checks that the material has no IGNITE_POINT defined. Furthermore, only bars, blocks, stone, logs, and anvils can be recognized as magma-safe - all other item types are considered unsafe, even if they are made of magma-safe materials.
In order to construct mechanisms from a magma-safe stone, simply ensure that they are the closest available stone to your mechanic, ideally by placing a restricted stockpile around your mechanic's workshop. Burrows can also be of assistance here, as dwarves will not attempt to pick up stone out side of their burrow assignments. However, if you have an active metalworking industry and have access to iron or steel, constructing metal mechanisms is much more straightforward.
When linking a trigger to an object, the first mechanism selected is attached to the object, and the second is attached to the trigger. Unless the trigger itself will be submerged in magma (as could be the case with a pressure plate), only the first mechanism (attached to the object that will be submerged) need be magma-safe. If you do not have any magma-safe stones available, you can also work around floodgate-based flow control by using screw pumps to pump the magma over wall-barriers, or using water to form obsidian to plug flows and channel through them to reopen them (necessity and invention and all that).
Constructions that resist magma are:
- Constructions (Wall, Floor, Ramp, and Stairs) of any material can never melt or burn - there is nothing wrong with a wooden magma reservoir. Natural (but not constructed) ice walls/floors/ramps/stairs may melt however.
- Fortifications will allow the passage of magma; however, if fortifications fill up to 7/7 depth, magma creatures will be able to swim freely through them.
- If not submerged (that is, not opened to let magma flow over/past/around them), doors, floodgates, and raised bridges (provided that there is no magma on the space the bridge would occupy when lowered) of non-magma-safe stone or metal are safe. So long as they are just in contact with magma, only acting as a passive "wall", they are fine. If opened, they will melt.
- Raised drawbridges have a notable exception, in that allowing magma to flow over the center of the area that the bridge would normally occupy when lowered will cause the bridge's components to heat up and potentially melt.
- A pump made with magma-safe metal pipes and screws and with magma-safe metal or stone blocks is fully magma-safe.
- A pump made with pipes and screws that are glass or any type of metalVerify, and blocks that are glass, or any type of metalVerify, is safe as long as no magma ever occupies the passable tile of the pump.
- Pumps made with wooden components will burst into flames the instant they are turned on.
- Pumps made with non-magma-safe stone blocks have been reported to melt after prolonged operation.
Glass behaves oddly in regards to magma. All types of glass are technically magma safe, based on a melting point of 13600 (the same as that of bauxite); however, small glass objects (such as instruments) seem to be instantly destroyed if dropped in magmaVerify. So glass statues, screw pumps, and floodgates are all fine when submerged in magma.
Glass barriers still require magma-proof mechanisms to operate without deconstructing.
 Game calculations
In the game, magma's temperature is exactly 12,000 °U, which is equivalent to 2,032°F, or about 1,111°C.
The chance of striking a magma-safe stone is roughly around 32%, not including the natural abundance of certain stone. It is important to note whether or not your fortress may already have access to magma-safe resources before attempting to deliberately find some.
 Magma-safe material
The following materials will not melt when submerged in magma. Although true for any item/construction, it's worth specifically mentioning that this includes doors, floor hatches, floodgates, bridges, screw pumps, and mechanisms.
|Type||Material||Appearance1||Melting Temperature °U (°F, °C)2||Found in||Uses / Notes|
||13,690°U (3722°F/2051°C)||All Igneous extrusive(L), Kaolinite(L)|
||12,610°U (2642°F/1450°C)||Gypsum(S), Satinspar(1), Alabaster(1), Selenite(1)|
||12,160°U (2192°F/1200°C)||Igneous extrusive layer stone|
||13,600°U (3632°F/2000°C)||All Sedimentary(L)||dark red|
||12,902°U (2934°F/1613°C)||Limestone(S), Marble(S)||flux stone|
||13,101°U (3133°F/1723°C)||Sedimentary layer stone|
||16,507°U (6539°F/3619°C)||Sedimentary layer stone||Flux|
||12,160°U (2192°F/1200°C)||Igneous intrusive layer stone|
||13,150°U (3182°F/1751°C)||All Sedimentary(L)||dark red, porcelain|
||12,295°U (2327°F/1275°C)||All Metamorphic(L), Granite(L)|
||13,600°U (3632°F/2001°C)||Igneous extrusive layer stone||value 3, can be "manufactured"|
||12,250°U (2282°F/1250°C)||All Igneous intrusive(L), All Metamorphic(L)||yellow|
||12,970°U (3002°F/1650°C)||All Sedimentary(S)||bright red|
||12,970°U (3002°F/1650°C)||Metamorphic layer stone|
||13,285°U (3214°F/1826°C)||All Metamorphic(S), Granite(S)||purple|
||12,070°U (2102°F/1149°C)||Sedimentary layer stone|
||25,000°U (15,032°F/8333°C)||Highest value/utility material in game|
||12,106°U (2138°F/1170°C)||used in steel making process|
||13,182°U (3214°F/1768°C)||High value metal|
||12,025°U (2057°F/1124°C)||Granite(V)||Ore of tin|
||12,005°U (2037°F/1113°C)||All Igneous extrusive(V), All Metamorphic(V), Granite(V), Limestone(V)||Ore of lead and silver|
||12,736°U (2768°F/1520°C)||All Sedimentary(V), All Igneous extrusive(V)||Ore of iron3|
||12,768°U (2800°F/1538°C)||All Sedimentary(L)||Ore of iron3|
||13,182°U (3214°F/1768°C)||Olivine(V), Magnetite(V), Chromite(S)||Ore of platinum|
||12,133°U (2165°F/1185°C)||All Metamorphic(V)||Ore of zinc4|
||N/A||Cavern (depth 3)||Naturally cold5|
||25,000°U (15,032°F/8333°C)||The depths||Ore of adamantine|
|Leather||Fire imp||15,000°U (5032°F/2780°C)|
|Bone||Fire imp||15,000°U (5032°F/2780°C)|
- 1. Each stone is one of 16 colors in the game. Different un-mined stone of the same color have a different symbol to distinguish between them. Once mined, the individual stones themselves can sometimes look identical if the color is the same. Use to loo at items or the terrain for specific information.
- 2. °U = degrees in Urist, the measure of temperature within the Dwarf Fortress world. As far as is known, there is no functional difference between a material that melts at 12,005°U or 55,000°U - they are both equally "magma safe".
- 3. There are three iron ores in the game (four if you count goblinite). Of these, only hematite and magnetite are magma safe.
- 4. Sphalerite has no melting point, but boils at 12,133°U. This still qualifies as being magma-safe.
- 5. Nether-cap logs have a fixed temperature of 10000°U or 0°C, rendering it fully magma safe, except that nether-cap products dumped into magma are destroyed.