Terry has suggested using artificial ivory for the white triangle bits. Timber would be very hard to use for that purpose, and it will never be white enough.
Searched the Web, found stuff on masecraftsupply.com. Ordered, and it has already arrived to our USA office today. Will be in Sydney in 10 days!

A friend came, looked at the corners assembly, and quickly pointed out that the pattern lines are broken making it look unnatural. After some hesitation, I concurred. Changed the design. Here is the new way (Same in all 4 corners):

Spent a day in the workshop experimenting with the ornament. Here is the day's result:

The corners are the hardest bit, so I spent most time on working out the corners.







I made a special jig for cutting the bits:

Made an experiment with cutting out a small fragment of the ornament. Terry helped by devising a rather sophisticated jig for his new dropsaw, The result is outstanding!

Richard the veneer-man has manufactured a few 'rainbow sandwiches'  made out of dozens of layers of different colors of veneer.

One of them came up pretty good:

This piece will be used for making the main feature of the ornament:

The other piece didn't come out terribly well. Richard will need to re-do it:

Spent time on digitizing the ornamental pattern of the inlay. Here:

The corners are not so easy to 'un-tangle'. So far looks ok to me.

Spent some time working on the ornament. Will be experimenting with laser cutting next week (http://www.smslaser.com.au, great professionals!)
According to SMS people, the laser beam is just 0.05mm, so I don't need to make any allowances for the thickness of the cut line.