My grandmother and grandfather were both born in the Netherlands. My
mother was born in Canada and has not claimed her citizenship to the
Netherlands (Holland).

Question: Am I eligible to claim Holland citizenship?

Dear Tosca, 

Before I begin with my answer, let me refer you again to the
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I'm afraid that you're not entitled to Dutch citizenship through
ancestry. Dutch citizenship is granted to children of Dutch citizens,
who have had lived in the Netherlands for a period before they've
applied. This might be relevant for your mother, shall she decide to
apply for a Dutch citizenship: after a year in the country, she could
apply for one. She would have to give up her current citizenship.

However, a son of a Dutch mother and a foreign father, who has been
born before 1985, is not entitled to Dutch citizenship; nor does the
Dutch government grant citizenship to grandchildren of Dutch
nationals. If you were born before 1985, or if your mother decides not
to go through the re-naturalisation process, you could not be entitled
to Dutch citizenship.

You could read more about it on the IND homepage: 
IND Residence Wizard
<http://www.ind.nl/EN/verblijfwijzer/verblijfwijzer_mijnsituatie.asp?proc=komen&lang=en&duur=1&procedure=Obtaining+Dutch+nationality>

It is possible, though, to gain Dutch citizenship after a few years of
residing legally in the Netherlands (first, of course, you will have
to apply for a temporary residence permit, which will turn into a
permanent one, and you could apply after five years of living legally
in the country). In such a case, you will have to give up your
Canadian citizenship. Read more about residence permits:
IND Residence Wizard: 
<http://www.ind.nl/EN/verblijfwijzer/verblijfwijzer_content.asp?proc=komen&lang=en>

I hope this answers your question. Please contact me if you need any
clarification on this answer before you rate it. My search strategy
was to search for terms related to the issue, such as [Dutch,
citizenship, consulate, immigration].