How many spell points does using an Admixture feat actually cost?

Question

When applying the Admixture talent and an Admixture feat to a destructive blast from the Destruction sphere, how many spell points does it actually cost?

For example, if I apply a Morphic Admixture, how many points am I spending? Assuming I do not spend any points to extend the shapeshift's duration.

It confuses me because both the talent and the feats cost a point, but the feats replace part of the talent's effects, raising the question whether you spend 1 point or 2 points.

This uses the versions following Ultimate Spheres of Power.

Admixture Talent from Destruction Sphere

Admixture

You may either increase the casting time of your destructive blast by one step or spend an additional spell point to apply two (blast type) talents instead of 1. The resultant blast does half of its damage of each type and any additional effects of the blast types are applied normally. If the die size for the two blasts are d8 and d6, use d8; if d8 and d4 use d6; if d6 and d4, use d4. If two blast types have different caster levels, then use the lower caster level for determining the admixtured blast’s caster level.

Special: You do not increase the casting time or spend an additional spell point when using the Admixture talent with two blast types from the same blast type group.

Admixture Feat Rules

Admixture feats grant new ways to utilize the Admixture talent (from the Destruction sphere), adding abilities from other spheres to your destructive blast. All admixture feats replace the second blast talent you would normally apply, with the resulting destructive blast dealing normal blast damage in addition to the effect outlined in the feat. Any additional costs incurred by the additional effect must be paid as normal. If your caster level is different for the two spheres, the destructive blast is governed by your caster level for the relevant blast type and the additional effect is governed by your caster level for the appropriate ability.

Morphic Admixture Feat

Morphic Admixture (Admixture)

Prerequisites: Alteration sphere, Destruction sphere (Admixture).

Benefit: When using Admixture, you may spend an additional spell point to have a single creature that takes damage save against a hostile shapeshift. If you possess the Mass Alteration talent, you may apply the hostile shapeshift to all targets damaged, up to your maximum targets from Mass Alteration.

Answer 1

Two Spell Points

One for admixture, and then the text of morphic admixture reads 'spend an additional spell point'. Additional here makes it clear that this is above and beyond any spell points you may have already spent. Admixture itself allows you to increase the casting time to avoid spending that initial spell point - Morphic Admixture has no such clause, and therefore always requires a spell point to be expended.