<xs:simpleType name="BitType">
  <xs:annotation>
    <xs:documentation>Specifies the values that represent the type of drill or core bit.</xs:documentation>
  </xs:annotation>
  <xs:restriction base="eml:TypeEnum">
    <xs:enumeration value="diamond">
      <xs:annotation>
        <xs:documentation>Diamond bit.</xs:documentation>
      </xs:annotation>
    </xs:enumeration>
    <xs:enumeration value="diamond core">
      <xs:annotation>
        <xs:documentation>Diamond core bit.</xs:documentation>
      </xs:annotation>
    </xs:enumeration>
    <xs:enumeration value="insert roller cone">
      <xs:annotation>
        <xs:documentation>Insert roller cone bit.</xs:documentation>
      </xs:annotation>
    </xs:enumeration>
    <xs:enumeration value="PDC">
      <xs:annotation>
        <xs:documentation>Polycrystalline diamond compact fixed-cutter bit.</xs:documentation>
      </xs:annotation>
    </xs:enumeration>
    <xs:enumeration value="PDC core">
      <xs:annotation>
        <xs:documentation>Polycrystalline diamond compact core bit.</xs:documentation>
      </xs:annotation>
    </xs:enumeration>
    <xs:enumeration value="roller cone">
      <xs:annotation>
        <xs:documentation>Milled-tooth roller-cone bit.</xs:documentation>
      </xs:annotation>
    </xs:enumeration>
  </xs:restriction>
</xs:simpleType>