...cherry leaves... autumn coloring... any help in guessing the name of the variety?

... my cherry tree, beside flowering beautifully and fruiting has one more lovely habit - its leaves are turning in reach yellow color in the autumn... you see here view from one of the windows... let's go outside and see how does it look...  

...looks beautiful, right? 

... I don't see many so yellow leaves on cherries in other gardens... not every variety  of sweet cherry has this surprising habit...

... this cherry tree is very old... maybe 20 years or more... no idea what is the name  of the variety...

.... do you have an idea what variety this could be? its fruits are very dark color, almost black... any idea?