Baa i cant work out how to put a pic on your thread so attached to a new one instead. This geranium is a oxonianum x sessiliflorum called Emily and its only source is Rosies garden plants. Your flower may be slightly darker than mine (it is pinker than in the photo) but the cross looks the same. The flowers are only approx 6mm across. Hope this helps.
Many thanks for the welcome.
Click the image for an enlarged view.
psilo Bolton, Greater Manc United Kingdom (Zone 8a)