diff --git a/src/simulation/elements/LITH.cpp b/src/simulation/elements/LITH.cpp
index 6afc69536..ad804c388 100644
--- a/src/simulation/elements/LITH.cpp
+++ b/src/simulation/elements/LITH.cpp
@@ -134,6 +134,10 @@ static int update(UPDATE_FUNC_ARGS)
 					break;
 
 				case PT_SPRK:
+					if (sim->parts_avg(i, ID(neighborData), PT_INSL) == PT_INSL)
+					{
+						break;
+					}
 					if (hydrogenationFactor + carbonationFactor >= 5)
 					{
 						continue; // too impure to do battery things.
@@ -145,6 +149,10 @@ static int update(UPDATE_FUNC_ARGS)
 					break;
 
 				case PT_NSCN:
+					if (sim->parts_avg(i, ID(neighborData), PT_INSL) == PT_INSL)
+					{
+						break;
+					}
 					if (neighbor.life == 0 && storedEnergy > 0 && !burnTimer)
 					{
 						sim->part_change_type(ID(neighborData), x + rx, y + ry, PT_SPRK);