diff --git a/core/field.js b/core/field.js
index 875828354..f88cbb8bc 100644
--- a/core/field.js
+++ b/core/field.js
@@ -63,17 +63,6 @@ Blockly.Field.prototype.visible_ = true;
  */
 Blockly.Field.prototype.changeHandler_ = null;
 
-/**
- * Clone this Field.  This must be implemented by all classes derived from
- * Field.  Since this class should not be instantiated, calling this method
- * throws an exception.
- * @throws {goog.assert.AssertionError}
- */
-Blockly.Field.prototype.clone = function() {
-  goog.asserts.fail('There should never be an instance of Field, ' +
-      'only its derived classes.');
-};
-
 /**
  * Non-breaking space.
  */
diff --git a/core/field_angle.js b/core/field_angle.js
index a8369f56e..56778a4b3 100644
--- a/core/field_angle.js
+++ b/core/field_angle.js
@@ -81,15 +81,6 @@ Blockly.FieldAngle.prototype.setChangeHandler = function(handler) {
   Blockly.FieldAngle.superClass_.setChangeHandler(wrappedHandler);
 };
 
-/**
- * Clone this FieldAngle.
- * @return {!Blockly.FieldAngle} The result of calling the constructor again
- *   with the current values of the arguments used during construction.
- */
-Blockly.FieldAngle.prototype.clone = function() {
-  return new Blockly.FieldAngle(this.getText(), this.changeHandler_);
-};
-
 /**
  * Round angles to the nearest 15 degrees when using mouse.
  * Set to 0 to disable rounding.
diff --git a/core/field_checkbox.js b/core/field_checkbox.js
index a1c15d395..1fe0332e2 100644
--- a/core/field_checkbox.js
+++ b/core/field_checkbox.js
@@ -48,15 +48,6 @@ Blockly.FieldCheckbox = function(state, opt_changeHandler) {
 };
 goog.inherits(Blockly.FieldCheckbox, Blockly.Field);
 
-/**
- * Clone this FieldCheckbox.
- * @return {!Blockly.FieldCheckbox} The result of calling the constructor again
- *   with the current values of the arguments used during construction.
- */
-Blockly.FieldCheckbox.prototype.clone = function() {
-  return new Blockly.FieldCheckbox(this.getValue(), this.changeHandler_);
-};
-
 /**
  * Mouse cursor style when over the hotspot that initiates editability.
  */
diff --git a/core/field_colour.js b/core/field_colour.js
index 69781a92a..18068f50e 100644
--- a/core/field_colour.js
+++ b/core/field_colour.js
@@ -67,15 +67,6 @@ Blockly.FieldColour.prototype.init = function(block) {
   this.setValue(this.getValue());
 };
 
-/**
- * Clone this FieldColour.
- * @return {!Blockly.FieldColour} The result of calling the constructor again
- *   with the current values of the arguments used during construction.
- */
-Blockly.FieldColour.prototype.clone = function() {
-  return new Blockly.FieldColour(this.getValue(), this.changeHandler_);
-};
-
 /**
  * Mouse cursor style when over the hotspot that initiates the editor.
  */
diff --git a/core/field_date.js b/core/field_date.js
index ffbdf143f..cabd1262f 100644
--- a/core/field_date.js
+++ b/core/field_date.js
@@ -57,15 +57,6 @@ Blockly.FieldDate = function(date, opt_changeHandler) {
 };
 goog.inherits(Blockly.FieldDate, Blockly.Field);
 
-/**
- * Clone this FieldDate.
- * @return {!Blockly.FieldDate} The result of calling the constructor again
- *   with the current values of the arguments used during construction.
- */
-Blockly.FieldDate.prototype.clone = function() {
-  return new Blockly.FieldDate(this.getValue(), this.changeHandler_);
-};
-
 /**
  * Mouse cursor style when over the hotspot that initiates the editor.
  */
diff --git a/core/field_dropdown.js b/core/field_dropdown.js
index a614e944b..2fa80bca4 100644
--- a/core/field_dropdown.js
+++ b/core/field_dropdown.js
@@ -71,15 +71,6 @@ Blockly.FieldDropdown.CHECKMARK_OVERHANG = 25;
  */
 Blockly.FieldDropdown.ARROW_CHAR = goog.userAgent.ANDROID ? '\u25BC' : '\u25BE';
 
-/**
- * Clone this FieldDropdown.
- * @return {!Blockly.FieldDropdown} The result of calling the constructor again
- *   with the current values of the arguments used during construction.
- */
-Blockly.FieldDropdown.prototype.clone = function() {
-  return new Blockly.FieldDropdown(this.menuGenerator_, this.changeHandler_);
-};
-
 /**
  * Mouse cursor style when over the hotspot that initiates the editor.
  */
diff --git a/core/field_image.js b/core/field_image.js
index 6e23bb541..6a4c70514 100644
--- a/core/field_image.js
+++ b/core/field_image.js
@@ -51,16 +51,6 @@ Blockly.FieldImage = function(src, width, height, opt_alt) {
 };
 goog.inherits(Blockly.FieldImage, Blockly.Field);
 
-/**
- * Clone this FieldImage.
- * @return {!Blockly.FieldImage} The result of calling the constructor again
- *   with the current values of the arguments used during construction.
- */
-Blockly.FieldImage.prototype.clone = function() {
-  return new Blockly.FieldImage(this.getSrc(), this.width_, this.height_,
-      this.getText());
-};
-
 /**
  * Rectangular mask used by Firefox.
  * @type {Element}
diff --git a/core/field_label.js b/core/field_label.js
index b2162b29b..fbf1ecb0b 100644
--- a/core/field_label.js
+++ b/core/field_label.js
@@ -45,15 +45,6 @@ Blockly.FieldLabel = function(text) {
 };
 goog.inherits(Blockly.FieldLabel, Blockly.Field);
 
-/**
- * Clone this FieldLabel.
- * @return {!Blockly.FieldLabel} The result of calling the constructor again
- *   with the current values of the arguments used during construction.
- */
-Blockly.FieldLabel.prototype.clone = function() {
-  return new Blockly.FieldLabel(this.getText());
-};
-
 /**
  * Editable fields are saved by the XML renderer, non-editable fields are not.
  */
diff --git a/core/field_textinput.js b/core/field_textinput.js
index 858e4bcad..dd84752c1 100644
--- a/core/field_textinput.js
+++ b/core/field_textinput.js
@@ -49,15 +49,6 @@ Blockly.FieldTextInput = function(text, opt_changeHandler) {
 };
 goog.inherits(Blockly.FieldTextInput, Blockly.Field);
 
-/**
- * Clone this FieldTextInput.
- * @return {!Blockly.FieldTextInput} The result of calling the constructor again
- *   with the current values of the arguments used during construction.
- */
-Blockly.FieldTextInput.prototype.clone = function() {
-  return new Blockly.FieldTextInput(this.getText(), this.changeHandler_);
-};
-
 /**
  * Mouse cursor style when over the hotspot that initiates the editor.
  */
diff --git a/core/field_variable.js b/core/field_variable.js
index 6d0a0dd17..7880fdbfb 100644
--- a/core/field_variable.js
+++ b/core/field_variable.js
@@ -101,15 +101,6 @@ Blockly.FieldVariable.prototype.init = function(block) {
   Blockly.FieldVariable.superClass_.init.call(this, block);
 };
 
-/**
- * Clone this FieldVariable.
- * @return {!Blockly.FieldVariable} The result of calling the constructor again
- *   with the current values of the arguments used during construction.
- */
-Blockly.FieldVariable.prototype.clone = function() {
-  return new Blockly.FieldVariable(this.getValue(), this.changeHandler_);
-};
-
 /**
  * Get the variable's name (use a variableDB to convert into a real name).
  * Unline a regular dropdown, variables are literal and have no neutral value.