We bought a table and chairs from Ikea about 7 years ago. The table is a Bjursta and the chairs are the now-discontinued Gilbert. I remember we agonized at the time over whether to buy the beech or birch colour. I can't remember which we got and we now want to change the chairs for upholstered ones, which only seem to be available in birch?! Help?! How can I tell if we've got beech or birch and if it's beech, where can I find matching chairs? Thanks!