  In this paper we characterise cone points of arbitrary subsets of Euclidean
space. Given $E \subset \mathbb{R}^n$, $x \in E$ is a cone point of $E$ if and
only if \begin{align*}
  \int_{0}^1 \beta_{E}^{d,2}(B(x,r))^2 \frac{dr}{r} < \infty, \end{align*} up
to a set of zero $d$-measure. The coefficients $\beta_E^{d,2}$ are a variation
of the Jones coefficients. This is a high dimensional counterpart of a theorem
of Bishop and Jones from 1994. We also prove similar results for
$\alpha$-paraboloid points, which are the $C^{1,\alpha}$ rectifiability
counterparts to cone points: $x \in E$ is an $\alpha$-paraboloid point if and
only if \begin{align*}
  \int_0^1 \frac{\overline{\beta}_{E}^{d,2}(B(x,r))^2}{r^{2\alpha}} \,
\frac{dr}{r} < \infty \end{align*} up to a set of zero $d$-measure. Here,
$\overline{\beta}^{d,2}_E$ is another variant of the Jones coefficients,
introduced by Azzam and Schul.
