diff --git a/src/calibre/db/write.py b/src/calibre/db/write.py
index 6025bbad9b..7207c268bc 100644
--- a/src/calibre/db/write.py
+++ b/src/calibre/db/write.py
@@ -111,7 +111,7 @@ def adapt_languages(to_tuple, x):
 
 def clean_identifier(typ, val):
     typ = icu_lower(typ or '').strip().replace(':', '').replace(',', '')
-    val = (val or '').strip().replace(',', '|').replace(':', '|')
+    val = (val or '').strip().replace(',', '|')
     return typ, val
 
 def adapt_identifiers(to_tuple, x):
diff --git a/src/calibre/ebooks/metadata/book/base.py b/src/calibre/ebooks/metadata/book/base.py
index bacf10dc73..1eab61ec63 100644
--- a/src/calibre/ebooks/metadata/book/base.py
+++ b/src/calibre/ebooks/metadata/book/base.py
@@ -47,7 +47,7 @@ def reset_field_metadata():
     field_metadata = FieldMetadata()
 
 ck = lambda typ: icu_lower(typ).strip().replace(':', '').replace(',', '')
-cv = lambda val: val.strip().replace(',', '|').replace(':', '|')
+cv = lambda val: val.strip().replace(',', '|')
 
 class Metadata(object):
 
diff --git a/src/calibre/gui2/metadata/basic_widgets.py b/src/calibre/gui2/metadata/basic_widgets.py
index a0f4fe6586..801907b7cd 100644
--- a/src/calibre/gui2/metadata/basic_widgets.py
+++ b/src/calibre/gui2/metadata/basic_widgets.py
@@ -1264,11 +1264,12 @@ class IdentifiersEdit(QLineEdit):  # {{{
                 c = x.split(':')
                 if len(c) > 1:
                     itype = c[0].lower()
+                    c = ':'.join(c[1:])
                     if itype == 'isbn':
-                        v = check_isbn(c[1])
+                        v = check_isbn(c)
                         if v is not None:
-                            c[1] = v
-                    ans[itype] = c[1]
+                            c = v
+                    ans[itype] = c
             return ans
         def fset(self, val):
             if not val: