unmeltable
Refuses to liquefy
Unmeltable describes something that cannot be melted—resistant to liquefying under heat.
The term applies literally to materials with extremely high melting points or figuratively to things that remain solid or unchanged: an unmeltable resolve, The glacier seemed unmeltable until climate change proved otherwise.
Unaffected by high temperatures
- fireproofUnable to ignite
- flame-retardantInhibits ignition and burning
- refractoryResistant to heat/control
- nonflammableUnable to burn
fire-resistant · heat-resistant · infusible · thermostable · firebrick · crucible · kiln-fired · high-temperature
Crystallized carbon gemstone
- tungstenElement seventy-four
- titaniumElement twenty-two
- steelCarbon-hardened iron alloy
- graniteIgneous rock, quartz-rich
quartz · obsidian · carbide · adamantine · crystalline · solidified · tempered · hardened
Lasting without end
- everlastingLasting for all time
- perpetualLasting without interruption
- immutableIncapable of being changed
- timelessUnaffected by eras
enduring · unchanging · constant · abiding · lasting · persistent · unfading · irreversible
Stubbornly refusing to yield
- invulnerableImmune to all harm
- imperviousUnable to be affected
- unbreakableImpossible to damage
- unyieldingRefusing to give way
invincible · resilient · impenetrable · indomitable · imperishable · nonperishable · armored · fortified
heatproof
Unaffected by high temperatures
- fireproofUnable to ignite
- flame-retardantInhibits ignition and burning
- refractoryResistant to heat/control
nonflammable · fire-resistant · heat-resistant · infusible · thermostable · firebrick · crucible · kiln-fired · high-temperature · tungsten
diamond
Crystallized carbon gemstone
granite · quartz · obsidian · carbide · adamantine · crystalline · solidified · tempered · hardened · rigid
eternal
Lasting without end
- everlastingLasting for all time
- perpetualLasting without interruption
- immutableIncapable of being changed
timeless · enduring · unchanging · constant · abiding · lasting · persistent · unfading · irreversible · indelible
adamant
Stubbornly refusing to yield
- invulnerableImmune to all harm
- imperviousUnable to be affected
- unbreakableImpossible to damage
unyielding · invincible · resilient · impenetrable · indomitable · imperishable · nonperishable · armored · fortified · reinforced
cold-hearted
Devoid of empathy
unmoved · impassive · stoic · unfeeling · frigid · frosty · glacial · heartless · unyielding · resolute
unmeltablemeltable
Able to be liquefied
fusible · liquefiable · low-melting · dissolvable · ice
melt, melted, melting, meltdown, smelting, meltwater, melter, unmelted, meltable