(MB) Base metals on the London Metal Exchange were split at the close of trading on Tuesday May 1, with copper, zinc and lead ending the day lower due to pressure from a stronger dollar index. Spot zinc concentrate treatment charges basis cif to major East Asian ports remained flat while lead concentrate terms declined marginally in April. Chinese ferro-vanadium exporters increased their offer prices in the week ended April 27 amid recovering prices in Europe, while US ferro-vanadium prices stagnated due to inactivity in the spot market. Read more in our Global Vanadium Wrap. The 250,000-tonne-per-year pipe mill of United Arab Emirates-based Conares Steel started production on April 29, chief executive officer Bharat Bhatia told Metal Bulletin. Prices for domestic steel rebar and imported steel billet in the United Arab Emirates decreased this week on poor demand, sources told Metal Bulletin. Flat steel import prices in the United Arab Emirates and Saudi Arabia remained unchanged this week due to limited demand, sources told Metal Bulletin. Holidays in Turkey and across much of Europe for the traditional May 1 Labor Day resulted in no change in prices for Turkish imports of deep-sea scrap from European and US suppliers, sources said.