diff --git a/src/buildCommon.js b/src/buildCommon.js
index 1a15ef51..e8f39453 100644
--- a/src/buildCommon.js
+++ b/src/buildCommon.js
@@ -238,7 +238,8 @@ const makeOrd = function<NODETYPE: "spacing" | "mathord" | "textord">(
     if (value.charCodeAt(0) === 0xD835) {
         // surrogate pairs get special treatment
         const [wideFontName, wideFontClass] = wideCharacterFont(value, mode);
-        return makeSymbol(value, wideFontName, mode, options, [wideFontClass]);
+        return makeSymbol(value, wideFontName, mode, options,
+            classes.concat(wideFontClass));
     } else if (fontOrFamily) {
         let fontName;
         let fontClasses;
diff --git a/test/katex-spec.js b/test/katex-spec.js
index 406421a3..eb351deb 100644
--- a/test/katex-spec.js
+++ b/test/katex-spec.js
@@ -1548,6 +1548,16 @@ describe("An HTML font tree-builder", function() {
         expect(markup).toContain(span);
     });
 
+    it("should render wide characters with mord and with the correct font", function() {
+        const markup = katex.renderToString(String.fromCharCode(0xD835, 0xDC00));
+        expect(markup).toContain("<span class=\"mord mathbf\">A</span>");
+
+        const phrase1 = getBuilt(String.fromCharCode(0xD835, 0xDC00) +
+            " = " + String.fromCharCode(0xD835, 0xDC1A))[0];
+        const phrase2 = getBuilt("\\mathbf A = \\mathbf a")[0];
+        expect(phrase1).toEqual(phrase2);
+    });
+
     it("should throw TypeError when the expression is of the wrong type", function() {
         expect(function() {
             katex.renderToString({badInputType: "yes"});