Mart(h)a van Uiter

Marta was born a slave. In the death certificate from her daughter Lambertina Calvenhoven, she was named Martha van Uiter. But orginally only Martha daugther of Ariette, born 1797. Before 1863 slaves didn't have a surname...

In the slave registry entry of owner Willem Craneveldt Hoyer, there are 5 children with Martha as their mother. Two children, Lambertina and Leonora were born in 1819 and 1821. Petroni was born in 1834, 13 years later and Lucien and Amalia a little later in 1837 and 1838.

Despite the interval of 13 years between Leonara and Petroni, I think there is only one Martha.

The mother of Martha - mother of Lucien , Petroni and Amalia - is definitely Arietta, as it was written in the slave register of owner Willem Cranenveldt Hoyer. Martha and here children were later sold to van Koevenhoven at feb 1842.

Abraham Daniel Cornelis van Koevenhoven (also van Coevenhoven) is the son in law of Willem Cranenveldt Hoyer. It could well be that Van Koevenhoven lived in the same house as Willem Cranenveldt Hoyer, but that must be researched further.
In that case it is merely an administrative issue and this slave family never moved.

What about Leonora and Lambertina? Leonora has a child named Constantia Henrietta. I you wish, you could imagine that she was named after Arietta.

With these three arguments I think we can conclude for the time being, that both Martha's are the same period, although it is still strange that there were no children born (even stillborns and short lived children, were mentioned in the slave registers) during 13 years.

At 20 October 1855 Martha was freed. No longer a slave. She is then 58 years old. (Source: Free letter, no 70). There is no other free letter for another Martha before 1863. One option is to look into the resume of 1863 of the slaves of Abraham Daniel Cornelis van Coevenhoven at the time of abolition of slavery and see if another Martha is mentioned. If none, then we know for sure, there was only 1 Martha.

Surname
In the death certificate of Maria Leonora Kalvenhoven (I think Maria was prefixed after christening), her mother Martha was named Martha van Uiter. This is interesting. The slave surname "Van Uiter" is named after the slave owners family "van Uytrecht". In the slave registry of Hoyer and Coevenhoeven, no exact birthdate or acquiring date was mentioned. Maybe in the slave registry of the family van Uytrecht, Martha could be found. Same applies for Lambertina and Leonora. [Things TODO]