I recently noticed a post mentioning that C.W.Warren and Co had made gravestones and memorials.
This enlarged part of the picture was taken probably shortly after the death of my great grandmother Ching Ah Fung aka Ellen Olson in 1915 judging from the floral tributes and is close to her husband John Olson aka Jons Jacobsson in Happy Valley. He died in 1918.
The picture shows the right hand corner which bears the mark C.E.W.and Co HK.
Interestingly my great grandfather's grave - which seems to be of the same design - only bears a number which is either 5284 or 3284 - in this position. Therefore probably not a Warren product. That picture was taken in 1918 and also shows floral tributes.
Both these pictures are in my family's possession and are now nearly 100 years old.