diff --git a/TrimSPlib.js b/TrimSPlib.js
index 9170096..b25d4f6 100644
--- a/TrimSPlib.js
+++ b/TrimSPlib.js
@@ -814,6 +814,7 @@ var rhos = {
     "MgO":3.58,
     "YBa2Cu3O7":6.54,
     "GaAs":5.32,
+    "SiN":3.17,
     "C60":1.65
 }