Greenstone spruiks investment grading 16 August 2010 4:37PM Ian Rogers Greenstone Energy is marketing NZ$100 million of bonds through a retail offer that commenced on Friday. It is the first public debt offering from a business that acquired the retail and distribution business of Shell in New Zealand in April. The interest rate on the six-year bonds was set at 7.35 per cent, though Greenstone will have the option of calling the bonds after three years. The bonds have no credit rating, though representatives for First NZ Capital, one of the investment banks marketing the bonds, tout them in investor presentations as being "at, or about, investment grade", the Dominion Post reported on Saturday.ANZ is also marketing the bonds for Greenstone.