This should do the job:
obs1 = observations(1);
Ncons = 1;
for i = 2:numel(observations)
if observations(i) == obs1
Ncons = Ncons + 1;
if Ncons == 60, break; end
else
obs1 = observations(i);
Ncons = 1;
end
end
if Ncons == 60
disp('60 consecutive prices found.')
end