Dierma, Angels Fishing Rods, springs to mind but more information would be useful, please, Guest.

I thought Dierama only came in pinks & purples Bulbaholic?

Maybe it's one of these, they are all taken from
http://www.meadowgatenursery.co.uk/ornamental-grass.htm

Miscanthus sinensis ‘Cosmopolitan’
A great ornamental grass for use architecturally, its foliage has deep green centres with creamy white margins. Copper red flowers emerging in late summer. Sunny open spot. Height approximately 2m. Semi-evergreen.

Miscanthus sinensis ‘Gracillimus’
Elegant narrow green leaves with a white stripe along the midrib. Copper red flower spikes may appear in late summer. Winter interest from the foliage changing to a bleached beige. Full sun. Height 2m approx. Semi-evergreen.

Molinia caerulea ‘Transparent’
Purple Moor Grass. A clump forming ornamental grass with arching foliage and dainty purplish plumes appearing in summer. Interest is provided late into the year as the flowers take on warm golden tones in autumn. Full sun, partial shade on well drained moist soil. Height 1.5 to 2m. Deciduous.

red hot poker sort of fits the description too.

And so do some of the better crocosmias