diff --git a/lib/spreadsheet/encodings.rb b/lib/spreadsheet/encodings.rb
index fd9ace3..f6f305a 100644
--- a/lib/spreadsheet/encodings.rb
+++ b/lib/spreadsheet/encodings.rb
@@ -35,13 +35,13 @@ def client string, internal='UTF-16LE'
       def internal string, client=Spreadsheet.client_encoding
         string = string.dup
         key = ['UTF-16LE', client]
-        iconv = @@iconvs[key] ||= Iconv.new('UTF-16LE', client)
+        iconv = @@iconvs[key] ||= Iconv.new('UTF-16LE//TRANSLIT//IGNORE', client)
         iconv.iconv string
       end
       def utf8 string, client=Spreadsheet.client_encoding
         string = string.dup
         key = ['UTF-8', client]
-        iconv = @@iconvs[key] ||= Iconv.new('UTF-8', client)
+        iconv = @@iconvs[key] ||= Iconv.new('UTF-8//TRANSLIT//IGNORE', client)
         iconv.iconv string
       end
     end