Balancing - Mining materials exports (#19470)

Added the ability to sell off your mining materials for profit. All
prices are relatively low, so it shouldn't mess up the balance of things
too much.
Consequentially, engineering can now sell its gold, silver, and platinum
to operations.
Also, I removed market elasticity from this materials list. Just to make
things far more consistent, and remove any potential and needless
frustration.
Thank you to @BoomerThor for helping me through this!

code/modules/cargo/exports/materials.dm

@@ -1,5 +1,6 @@
 /datum/export/material
 	cost = 5 // Cost per MINERAL_MATERIAL_AMOUNT, which is 2000cm3 as of April 2016.
+	k_elasticity = 0
 	message = "cm3 of developer's tears. Please, report this on github"
 	var/material_id = null
 	export_types = list(/obj/item/stack/material/)
@@ -15,46 +16,97 @@
 
 	return M.amount
 
-// Materials. Nothing but Phoron is really worth selling. Better leave it all to RnD.
+// Materials. As of writing in 2024, this list was small, and most everything was effected by price elasticity. Now, it's been rebalanced. Price elasticity was removed,
+// and more materials now have values. These materials are mainly concerend with mining.
+
 
 /datum/export/material/diamond
-	cost = 100
+	cost = 20
 	material_id = "diamond"
 	message = "diamond sheets"
 
 /datum/export/material/phoron
 	cost = 175
-	k_elasticity = 0
 	material_id = "phoron"
 	message = "phoron sheets"
 
 /datum/export/material/uranium
-	cost = 10
+	cost = 8
 	material_id = "uranium"
 	message = "uranium sheets"
 
 /datum/export/material/gold
-	cost = 25
+	cost = 12
 	material_id = "gold"
 	message = "gold sheets"
 
 /datum/export/material/silver
-	cost = 10
+	cost = 8
 	material_id = "silver"
 	message = "silver sheets"
 
 /datum/export/material/platinum
-	cost = 20
+	cost = 12
 	material_id = "platinum"
 	message = "platinum sheets"
 
+/datum/export/material/osmium
+	cost = 24
+	material_id = "osmium"
+	message = "osmium bars"
+
 /datum/export/material/metal
-	cost = 5
+	cost = 2
 	material_id = "metal"
 	message = "metal sheets"
 
+/datum/export/material/steel
+	cost = 1
+	material_id = "steel"
+	message = "steel sheets"
+
+/datum/export/material/plasteel
+	cost = 20
+	material_id = "plasteel"
+	message = "plasteel sheets"
+
+/datum/export/material/iron
+	cost = 1
+	material_id = "iron"
+	message = "iron ingots"
+
+/datum/export/material/plastic
+	cost = 1
+	material_id = "plastic"
+	message = "plastic sheets"
+
+/datum/export/material/graphite
+	cost = 2
+	material_id = "graphite"
+	message = "graphite bars"
 
 /datum/export/material/glass
-	cost = 5
+	cost = 1
 	material_id = "glass"
 	message = "glass sheets"
+
+/datum/export/material/tritium
+	cost = 5
+	material_id = "tritium"
+	message = "tritium ingots"
+
+/datum/export/material/mhydrogen
+	cost = 10
+	material_id = "mhydrogen"
+	message = "metallic hydrogen sheets"
+
+/datum/export/material/aluminium
+	cost = 3
+	material_id = "aluminium"
+	message = "aluminium sheets"
+
+/datum/export/material/lead
+	cost = 3
+	material_id = "lead"
+	message = "lead sheets"
+

code/modules/cargo/exports/sheets.dm

@@ -40,12 +40,6 @@
 
 // Common materials.
 // For base materials, see materials.dm
-
-/datum/export/stack/plasteel
-	cost = 155 // 2000u of plasma + 2000u of metal.
-	message = "of plasteel"
-	export_types = list(/obj/item/stack/material/plasteel)
-
 // 1 glass + 0.5 metal, cost is rounded up.
 /datum/export/stack/rglass
 	cost = 8