diff --git a/mods/Unuennium.js b/mods/Unuennium.js
new file mode 100644
index 00000000..56044929
--- /dev/null
+++ b/mods/Unuennium.js
@@ -0,0 +1,41 @@
+var modName = "mods/ununennium.js";
+var libraryMod = "mods/code_library.js";
+
+if (enabledMods.includes(libraryMod)) {
+
+    elements.ununennium = {
+        color: "#d1d1ff", // pale bluish tone
+        behavior: behaviors.LIQUID,
+        reactions: {
+            "hydrogen": { elem1: "oxygen", elem2: null }
+        },
+        tempHigh: -156, // Celsius
+        stateHigh: "gaseous_ununennium",
+        tempLow: -231,
+        stateLow: "solid_ununennium",
+        category: "liquids",
+        state: "liquid",
+        density: 13500, // Heavy synthetic element
+    };
+
+    elements.solid_ununennium = {
+        color: "#a8a8ff",
+        behavior: behaviors.SOLID,
+        temp: -232,
+        category: "solids",
+        state: "solid",
+        density: 13800,
+        hidden: true
+    };
+
+    elements.gaseous_ununennium = {
+        color: "#e0e0ff",
+        behavior: behaviors.GAS,
+        temp: -155,
+        category: "gases",
+        state: "gas",
+        density: 0.05,
+        hidden: true
+    };
+
+}