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Difference between revisions of "v0.34:Magma-safe"

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(→‎Magma-safe material: sphalerite is definitely magma-safe - at 12000, it's still solid, not flammable, and doesn't take hot/cold damage)
(This was a very confusing sentence that contradicted the rest of the page. We can discuss its deletion on the talk session if someone wants it back.)
 
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{{quality|Exceptional|10:15, 12 August 2010 (UTC)}}{{av}}
 
{{quality|Exceptional|10:15, 12 August 2010 (UTC)}}{{av}}
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{{Material properties}}
 +
'''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 [[floodgate]]s operated by [[mechanism]]s, or when operating a [[screw pump|magma pump]].
  
'''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 [[floodgate]]s operated by [[mechanism]]s.
+
For [[reaction]]s and custom buildings using the [MAGMA_BUILD_SAFE] token, only a material which is solid and stable at the temperature {{ct|12000}} (i.e. MELTING_POINT/BOILING_POINT/IGNITE_POINT/HEATDAM_POINT greater than 12000 and COLDDAM_POINT less than 12000) is considered magma-safe.  
  
For [[reaction]]s and custom buildings using the [MAGMA_BUILD_SAFE] token, only a material which is solid and stable at the temperature {{ct|12000}} (i.e. MELTING_POINT/BOILING_POINT/IGNITE_POINT/HEATDAM_POINT greater than 12000 and COLDDAM_POINT less than 12000) is considered magma-safe. Furthermore, only [[bar]]s, [[block]]s, [[stone]], [[log]]s, and [[anvil]]s 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, blocks or other pump components from a magma-safe material, you have several choices:
 +
# Build your [[mechanism]]s out of [[iron]] or [[steel]].
 +
# Build your pump components out of iron, steel, [[glass]], or [[nether-cap]].
 +
# Place a [[stockpile]] with the desired stones around your [[mechanic's workshop]] and set it to "Give To a Pile/Workshop".
 +
# Use a [[burrow]] that contains only the workshop and the desired materials.
 +
# Simply ensure that the desired materials are the closest available to your worker. This does not always work, but is usually good enough if you request several jobs, hoping that at least one uses the correct material.
  
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]]. [[Burrow]]s 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) needs to 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 pump]]s 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).
 
 
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 pump]]s 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).
 
  
 
This property is also relevant when choosing the appropriate method for disposing of unneeded items, which can impact [[FPS]] when in large numbers. Items made of non magma-safe materials can be simply dumped into magma, which is the easiest disposal method; however, magma-safe items will need more [[Dwarven atom smasher|drastic]] measures.
 
This property is also relevant when choosing the appropriate method for disposing of unneeded items, which can impact [[FPS]] when in large numbers. Items made of non magma-safe materials can be simply dumped into magma, which is the easiest disposal method; however, magma-safe items will need more [[Dwarven atom smasher|drastic]] measures.
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Constructions that resist magma are:
 
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 [[wood]]en magma reservoir.  Natural (but not constructed) [[ice]] walls/floors/ramps/stairs may melt however.
+
* Constructions ([[Wall]], [[Floor]], [[Ramp]], and [[Stairs]]) of any material can never melt or burn - there is nothing wrong with a [[wood]]en magma reservoir.  Natural (i.e. non-constructed) [[ice]] walls/floors/ramps/stairs will melt if exposed to sufficient heat.
 
* [[Fortification]]s 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.
 
* [[Fortification]]s 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), [[door]]s, [[floodgate]]s, and raised [[bridge]]s (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.
 
* If not submerged (that is, not opened to let magma flow over/past/around them), [[door]]s, [[floodgate]]s, and raised [[bridge]]s (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.
 
** 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 magma-safe material for pipes, screws and blocks is fully magma-safe, and will not melt even when submerged in magma. Pumps containing any item that is not magma safe will be destroyed after prolonged operation.
* A [[pump]] made with pipes and screws that are glass or any type of metal{{Verify}}, and blocks that are glass, or any type of metal{{Verify}}, is safe as long as no magma ever occupies the passable tile of the pump.
 
* [[Pump]]s made with [[wood]]en components will burst into flames the instant they are turned on.
 
* [[Pump]]s made with non-magma-safe stone blocks have been reported to melt after prolonged operation.
 
  
 
== Game calculations ==
 
== Game calculations ==
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-->
 
-->
 
 
{{MS table head}}
 
{{MS table head}}
  
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{{MS table row|Type=Stone|Matl=[[Chromite]]|Appear={{Raw Tile|=|0:7:1}} {{Raw Tile|•|0:1}}|Temp=13,645°U (3677°F/2026°C)|Where=[[Olivine]]'''(V)'''}}
 
{{MS table row|Type=Stone|Matl=[[Chromite]]|Appear={{Raw Tile|=|0:7:1}} {{Raw Tile|•|0:1}}|Temp=13,645°U (3677°F/2026°C)|Where=[[Olivine]]'''(V)'''}}
  
{{MS table row|Type=Stone|Matl=[[Dolomite]]|Appear={{Raw Tile|`|7:7:1}} {{Raw Tile|•|7:1}}|Temp=16,507°U (6539°F/3619°C)|Where=[[Sedimentary]] layer stone|Notes=[[Flux]]}}
+
{{MS table row|Type=Stone|Matl=[[Dolomite]]|Appear={{Raw Tile|`|7:7:1}} {{Raw Tile|•|7:1}}|Temp=16,507°U (6539°F/3619°C)|Where=[[Sedimentary]] layer stone|Notes=[[Flux]], Highest melting point of any common stone.}}
  
 
{{MS table row|Type=Stone|Matl=[[Gabbro]]|Appear={{Raw Tile|▒|0:7:1}} {{Raw Tile|•|0:1}}|Temp=12,160°U (2192°F/1200°C)|Where=[[Igneous intrusive]] layer stone}}
 
{{MS table row|Type=Stone|Matl=[[Gabbro]]|Appear={{Raw Tile|▒|0:7:1}} {{Raw Tile|•|0:1}}|Temp=12,160°U (2192°F/1200°C)|Where=[[Igneous intrusive]] layer stone}}
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{{MS table row|Type=Stone|Matl=[[Talc]]|Appear={{Raw Tile|||7:7:1}} {{Raw Tile|•|7:1}}|Temp=12,700°U (2732°F/1500°C)|Where=[[Dolomite]]'''(L)'''}}
 
{{MS table row|Type=Stone|Matl=[[Talc]]|Appear={{Raw Tile|||7:7:1}} {{Raw Tile|•|7:1}}|Temp=12,700°U (2732°F/1500°C)|Where=[[Dolomite]]'''(L)'''}}
  
{{MS table row|Type=Metal|Matl=[[Adamantine]]|Appear={{Raw Tile||3:3:1}} {{Raw Tile|≡|3:1}}|Temp=25,000°U (15,032°F/8333°C)|Notes=Highest value/utility material in game}}
+
{{MS table row|Type=Metal|Matl=[[Adamantine]]|Appear={{Raw Tile|X|3:3:1}} {{Raw Tile|≡|3:1}}|Temp=25,000°U (15,032°F/8333°C)|Notes=Highest value/utility material in game}}
  
{{MS table row|Type=Metal|Matl=[[Iron]]|Appear={{Raw Tile||0:7:1}} {{Raw Tile|≡|0:1}}|Temp=12,768°U (2800°F/1538°C)}}
+
{{MS table row|Type=Metal|Matl=[[Iron]]|Appear={{Raw Tile|X|0:7:1}} {{Raw Tile|≡|0:1}}|Temp=12,768°U (2800°F/1538°C)}}
  
{{MS table row|Type=Metal|Matl=[[Nickel]]|Appear={{Raw Tile||7:3:0}} {{Raw Tile|≡|7:0}}|Temp=12,619°U (2651°F/1455°C)}}
+
{{MS table row|Type=Metal|Matl=[[Nickel]]|Appear={{Raw Tile|X|7:3:0}} {{Raw Tile|≡|7:0}}|Temp=12,619°U (2651°F/1455°C)}}
  
{{MS table row|Type=Metal|Matl=[[Pig iron]]|Appear={{Raw Tile||0:7:1}} {{Raw Tile|≡|0:1}}|Temp=12,106°U (2138°F/1170°C)|Notes=used in steel making process}}
+
{{MS table row|Type=Metal|Matl=[[Pig iron]]|Appear={{Raw Tile|X|0:7:1}} {{Raw Tile|≡|0:1}}|Temp=12,106°U (2138°F/1170°C)|Notes=used in steel making process}}
  
{{MS table row|Type=Metal|Matl=[[Platinum]]|Appear={{Raw Tile||7:7:1}} {{Raw Tile|≡|7:1}}|Temp=13,182°U (3214°F/1768°C)|Notes=High value metal}}
+
{{MS table row|Type=Metal|Matl=[[Platinum]]|Appear={{Raw Tile|X|7:7:1}} {{Raw Tile|≡|7:1}}|Temp=13,182°U (3214°F/1768°C)|Notes=High value metal}}
  
{{MS table row|Type=Metal|Matl=[[Steel]]|Appear={{Raw Tile||0:7:1}} {{Raw Tile|≡|0:1}}|Temp=12,718°U (2750°F/1510°C)|Notes=Armor/weapons}}
+
{{MS table row|Type=Metal|Matl=[[Steel]]|Appear={{Raw Tile|X|0:7:1}} {{Raw Tile|≡|0:1}}|Temp=12,718°U (2750°F/1510°C)|Notes=Armor/weapons}}
  
 
{{MS table row|Type=Ore|Matl=[[Cassiterite]]|Appear={{Raw Tile|£|6:7:0}} {{Raw Tile|*|6:0}}|Temp=12,025°U (2057°F/1124°C)|Where=[[Granite]]'''(V)'''|Notes=Ore of [[tin]]}}
 
{{MS table row|Type=Ore|Matl=[[Cassiterite]]|Appear={{Raw Tile|£|6:7:0}} {{Raw Tile|*|6:0}}|Temp=12,025°U (2057°F/1124°C)|Where=[[Granite]]'''(V)'''|Notes=Ore of [[tin]]}}
Line 117: Line 118:
 
{{MS table row|Type=Bone|Matl=[[Dragon]]|Appear=|Temp=55,000°U (45032°F/25,044°C)|Notes=}}
 
{{MS table row|Type=Bone|Matl=[[Dragon]]|Appear=|Temp=55,000°U (45032°F/25,044°C)|Notes=}}
  
{{MS table row|Type=Glass|Matl=Green glass|Appear={{Raw Tile||2:2:1}} {{Raw Tile|■|2:0}}|Temp=13,600°U (3632°F/2001°C)|Notes=}}
+
{{MS table row|Type=Glass|Matl=[[Glass|Green glass]]|Appear={{Raw Tile|X|2:2:1}} {{Raw Tile|■|2:0}}|Temp=13,600°U (3632°F/2001°C)|Notes=}}
{{MS table row|Type=Glass|Matl=Clear glass|Appear={{Raw Tile||3:3:1}} {{Raw Tile|■|3:0}}|Temp=13,600°U (3632°F/2001°C)|Notes=}}
+
{{MS table row|Type=Glass|Matl=[[Glass|Clear glass]]|Appear={{Raw Tile|X|3:3:1}} {{Raw Tile|■|3:0}}|Temp=13,600°U (3632°F/2001°C)|Notes=}}
{{MS table row|Type=Glass|Matl=Crystal glass|Appear={{Raw Tile||7:7:1}} {{Raw Tile|■|7:1}}|Temp=13,600°U (3632°F/2001°C)|Notes=}}
+
{{MS table row|Type=Glass|Matl=[[Glass|Crystal glass]]|Appear={{Raw Tile|X|7:7:1}} {{Raw Tile|■|7:1}}|Temp=13,600°U (3632°F/2001°C)|Notes=}}
  
 
|}
 
|}
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:1. Each stone is one of 16 [[color scheme|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 {{k|k}} to loo{{k|k}} at items or the terrain for specific information.
 
:1. Each stone is one of 16 [[color scheme|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 {{k|k}} to loo{{k|k}} at items or the terrain for specific information.
 
:2. '''°U''' = degrees in [[Main:Urist|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 {{ct|12005}} or {{ct|55000}} — they are both equally "magma safe".
 
:2. '''°U''' = degrees in [[Main:Urist|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 {{ct|12005}} or {{ct|55000}} — they are both equally "magma safe".
:3. There are three iron ores in the game (four if you count [[goblin|goblinite]]). Of these, only [[hematite]] and [[magnetite]] are 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 ''sublimates'' at {{ct|12133}}. This still qualifies as being magma-safe.
 
:4. Sphalerite has ''no'' melting point, but ''sublimates'' at {{ct|12133}}. This still qualifies as being magma-safe.
 
:5. [[Nether-cap]] logs have a fixed temperature of {{ct|10000}}, rendering them fully magma safe, except that nether-cap products [[dump]]ed into magma are destroyed.
 
:5. [[Nether-cap]] logs have a fixed temperature of {{ct|10000}}, rendering them fully magma safe, except that nether-cap products [[dump]]ed into magma are destroyed.

Latest revision as of 03:11, 8 July 2014

This article is about an older version of DF.

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, or when operating a magma pump.

For reactions and custom buildings using the [MAGMA_BUILD_SAFE] token, only a material which is solid and stable at the temperature 12000 °U (i.e. MELTING_POINT/BOILING_POINT/IGNITE_POINT/HEATDAM_POINT greater than 12000 and COLDDAM_POINT less than 12000) is considered magma-safe.

In order to construct mechanisms, blocks or other pump components from a magma-safe material, you have several choices:

  1. Build your mechanisms out of iron or steel.
  2. Build your pump components out of iron, steel, glass, or nether-cap.
  3. Place a stockpile with the desired stones around your mechanic's workshop and set it to "Give To a Pile/Workshop".
  4. Use a burrow that contains only the workshop and the desired materials.
  5. Simply ensure that the desired materials are the closest available to your worker. This does not always work, but is usually good enough if you request several jobs, hoping that at least one uses the correct material.

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) needs to 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).

This property is also relevant when choosing the appropriate method for disposing of unneeded items, which can impact FPS when in large numbers. Items made of non magma-safe materials can be simply dumped into magma, which is the easiest disposal method; however, magma-safe items will need more drastic measures.

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 (i.e. non-constructed) ice walls/floors/ramps/stairs will melt if exposed to sufficient heat.
  • 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 material for pipes, screws and blocks is fully magma-safe, and will not melt even when submerged in magma. Pumps containing any item that is not magma safe will be destroyed after prolonged operation.

Game calculations[edit]

In the game, magma's temperature is exactly 12000 °U .

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[edit]

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
Stone Alunite ` 13,690°U (3722°F/2051°C) All Igneous extrusive(L), Kaolinite(L)
Stone Anhydrite v 12,610°U (2642°F/1450°C) Gypsum(S), Satinspar(1), Alabaster(1), Selenite(1)
Stone Basalt # 12,160°U (2192°F/1200°C) Igneous extrusive layer stone
Stone Bauxite + 13,600°U (3632°F/2000°C) All Sedimentary(L) dark red
Stone Calcite " 12,902°U (2934°F/1613°C) Limestone(S), Marble(S) flux stone
Stone Chert = 13,101°U (3133°F/1723°C) Sedimentary layer stone
Stone Chromite = 13,645°U (3677°F/2026°C) Olivine(V)
Stone Dolomite ` 16,507°U (6539°F/3619°C) Sedimentary layer stone Flux, Highest melting point of any common stone.
Stone Gabbro 12,160°U (2192°F/1200°C) Igneous intrusive layer stone
Stone Ilmenite . 12,457°U (2489°F/1365°C) Gabbro(S)
Stone Kaolinite = 13,150°U (3182°F/1751°C) All Sedimentary(L) dark red, porcelain
Stone Mica v 12,295°U (2327°F/1275°C) All Metamorphic(L), Granite(L)
Stone Obsidian 13,600°U (3632°F/2001°C) Igneous extrusive layer stone value 3, can be "manufactured"
Stone Olivine % 13,168°U (3200°F/1761°C) Gabbro(L) green
Stone Orthoclase % 12,250°U (2282°F/1250°C) All Igneous intrusive(L), All Metamorphic(L) yellow
Stone Periclase , 15,040°U (5072°F/2803°C) Marble(S)
Stone Petrified wood % 12,970°U (3002°F/1650°C) All Sedimentary(S) bright red
Stone Pitchblende * 12,070°U (2102°F/1149°C) Granite(S) purple
Stone Quartzite - 12,970°U (3002°F/1650°C) Metamorphic layer stone
Stone Rutile ` 13,285°U (3214°F/1826°C) All Metamorphic(S), Granite(S) purple
Stone Sandstone # 12,070°U (2102°F/1149°C) Sedimentary layer stone
Stone Talc | 12,700°U (2732°F/1500°C) Dolomite(L)
Metal Adamantine X 25,000°U (15,032°F/8333°C) Highest value/utility material in game
Metal Iron X 12,768°U (2800°F/1538°C)
Metal Nickel X 12,619°U (2651°F/1455°C)
Metal Pig iron X 12,106°U (2138°F/1170°C) used in steel making process
Metal Platinum X 13,182°U (3214°F/1768°C) High value metal
Metal Steel X 12,718°U (2750°F/1510°C) Armor/weapons
Ore Cassiterite £ * 12,025°U (2057°F/1124°C) Granite(V) Ore of tin
Ore Galena £ * 12,005°U (2037°F/1113°C) All Igneous extrusive(V), All Metamorphic(V), Granite(V), Limestone(V) Ore of lead and silver
Ore Hematite3 £ * 12,736°U (2768°F/1520°C) All Sedimentary(V), All Igneous extrusive(V) Ore of iron3
Ore Magnetite3 ~ * 12,768°U (2800°F/1538°C) All Sedimentary(L) Ore of iron3
Ore Native platinum £ * 13,182°U (3214°F/1768°C) Olivine(V), Magnetite(V), Chromite(S) Ore of platinum
Ore Sphalerite4 £ * 12,133°U (2165°F/1185°C) All Metamorphic(V) Ore of zinc4
Wood Nether-cap5 N/A Cavern (depth 3) Naturally cold5
Special Raw adamantine £ * 25,000°U (15,032°F/8333°C) The depths Ore of adamantine
Leather Fire imp 15,000°U (5032°F/2780°C)
Leather Dragon 55,000°U (45032°F/25,044°C) Dragon scales actually cannot be tanned
Bone Fire imp 15,000°U (5032°F/2780°C)
Bone Dragon 55,000°U (45032°F/25,044°C)
Glass Green glass X 13,600°U (3632°F/2001°C)
Glass Clear glass X 13,600°U (3632°F/2001°C)
Glass Crystal glass X 13,600°U (3632°F/2001°C)

Notes:

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 k to look 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 12005 °U or 55000 °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 sublimates at 12133 °U . This still qualifies as being magma-safe.
5. Nether-cap logs have a fixed temperature of 10000 °U , rendering them fully magma safe, except that nether-cap products dumped into magma are destroyed.