Hi Linda,
it's a really nice vase!

It seems to be an interesting amalgam of Victorian (the thorny vase part) & later styles (the applied feet).
Those type of applied feet (as you mentioned) appear on 1920s era Czech vases, which are sometimes referred to as "rocket vases". However, these vases are not usually seen in opalescent vaseline with thorns! They are more likely to be in opaque shades of orange, red, etc, & the applied "rocket" feet are typically opaque black or deep cobalt blue.
Victorian vases of this thorny type tend to have applied feet inspired by natural forms such as stylized leaves, rustic tree roots & so on.
So, the vase as I mentioned appears to be a blend of 2 styles. I would tentatively date it at early 20th century, say around 1900-1920, and definitely Czech in origin.