As most philatelists will know by now, the end of this month will see the first section of the glorious Chartwell collection of the British Empire go under the hammer.

However, that incredible accumulation may have drawn the eyes of collectors away from some desirable, and relatively affordable stamps and covers of the Commonwealth which may nevertheless count as strong alternative investments.

This is the Robert Towers collection of the British Empire, which goes under the hammer this Wednesday June 8 in London. Nearly 700 lots are on offer with an impressive variety of high quality examples.

Highlights include: a selection of 1861 Woodblocks from the Cape of Good Hope:  three 1d examples and 10 4d stamps including a very rare deep bright blue pair and one with retouch to right-hand corner.

All are used. Two of the 4d examples have with clear margins. These are expected to sell for £4,000-5,000 ($8,200).

There is also an interesting collection of 1854 used Indian stamps (£3,000-4,000), a selection of 1857 Ceylon stamps (£4,000-5,000) and a set of Mauritius 1848-59 'Post Paid' stamps (£2,000-3,000).

But some of the best of the whole sale hail from New Zealand, including a particularly exciting cover.

A beautiful bisect: the £10,000 New Zealand cover

Printed in Auckland on Blue Paper, it is a 1/- green marginal example from the left of the sheet, bisected vertically, clearly cancelled and tied on 1859 (25 January). It includes the entire letter, headed "East Waitahuna Station Molyneux" from Otago to Edinburgh.

The auctioneer suggests that this is probably the finest of either bisect recorded and the only one, from either this or the London print bisects, to have a sheet margin. Otago and Edinburgh circular date stamps appear on the reverse.

The cover is number 23 of the 26 recorded Richardson bisects reported by Gerald Ellott and R-23 from that recorded by Robert Odenweller. It is expected to sell for £5,000-10,000 ($16,400). Watch this space for the results of this intriguing auction.

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