diff --git a/ClosedXML_Tests/Excel/Cells/DataTypeTests.cs b/ClosedXML_Tests/Excel/Cells/DataTypeTests.cs
new file mode 100644
index 0000000..2808008
--- /dev/null
+++ b/ClosedXML_Tests/Excel/Cells/DataTypeTests.cs
@@ -0,0 +1,22 @@
+using ClosedXML.Excel;
+using NUnit.Framework;
+using System;
+
+namespace ClosedXML_Tests.Excel.Cells
+{
+    [TestFixture]
+    public class DataTypeTests
+    {
+        [Test]
+        public void ConvertNonNumericTextToNumberThrowsException()
+        {
+            using (var wb = new XLWorkbook())
+            {
+                var ws = wb.Worksheets.Add("Sheet1");
+                var c = ws.Cell("A1");
+                c.Value = "ABC123";
+                Assert.Throws<ArgumentException>(() => c.DataType = XLDataType.Number);
+            }
+        }
+    }
+}