Well, yes and no. "Value" is abstract instead of concrete, just like "mind" is abstract while "brain" is concrete.
Here's an analogy I've been working on: Take 3 pennies. Drop them on the table. What do you see? Four items: Three pennies and one triangle.
So, is the triangle physical? No, it's abstract. Does the triangle exist outside of the pennies? No, without the pennies the triangle wouldn't exist. So, if we drop the pennies into a vat of molten copper, so that the pennies cease to exist as such, what happens to the triangle? Does it fly off to a supernatural triangle storage pile to be used again? No, it ceases to exist just as the pennies themselves ceased to exist.
The triangle is an abstract aspect of the three pennies. And in exactly the same way (but infinitely more complex), the mind is the abstract aspect of a working physical brain. IOW an emergent property.
BTW, I suspect Rand would disagree with me about the triangles. I think she'd say that I was being intrincisist, and the triangle only exists as a concept in our minds. But I don't know, and she's not here to argue the point, so too bad for her! Anyway, here's what Peikoff says about Materialism vs. Idealism:
Now let us apply the principles we have been discussing to two outstanding falsehoods in the history of metaphysics: idealism and materialism.The idealists - figures such as Plato, Plotinus, Augustine, Hegel - regard reality as a spiritual dimension transcending and controlling the world of nature, which latter is regarded as deficient, ephemeral, imperfect - in any event, as only partly real. Since "spiritual," in fact, has no meaning other than "pertaining to consciousness," the content of true reality in this view is invariably some function or form of consciousness (e.g., Plato's abstractions, Augustine's God, Hegel's Ideas). This approach amounts to the primacy of consciousness and thus, as Ayn Rand puts it, to the advocacy of consciousness without existence.
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The more sophisticated versions of idealism rest on technical analyses of the nature of percepts or concepts, ... The unsophisticated but popular version of idealism, which typically upholds a personalized other dimension, is religion. Essential to all versions of the creed, however - and to countless kindred movements - is the belief in the supernatural.
"Supernatural," etymologically, means that which is above or beyond nature. "Nature," in turn, denotes existence viewed from a certain perspective. Nature is existence regarded as a system of interconnected entities governed by law; it is the universe of entities acting and interacting in accordance with their identities. What then is a "super-nature"? It would have to be a form of existence beyond existence; a thing beyond entities; a something beyond identity.
The idea of the "supernatural" is an assault on everything man knows about reality. It is a contradiction of every essential of a rational metaphysics. It represents a rejection of the basic axioms of philosophy....
[Every claim about God] leads to a contradiction of the axiomatic concepts of philosophy. At every point, the notion clashes with the facts of reality and with the preconditions of thought. ...
The point is broader than religion. It is inherent in any advocacy of a transcendent dimension. Any attempt to defend or define the supernatural must necessarily collapse in fallacies. There is no logic that will lead one from the facts of this world to a realm contradicting them....
This does not mean that Objectivists are materialists.
Materialists - men such as Democritus, Hobbes, Marx, Skinner - champion nature but deny the reality or efficacy of consciousness. Consciousness, in this view, is either a myth or a useless byproduct of brain or other motions. In Objectivist terms, this amounts to the advocacy of existence without consciousness. It is the denial of man's faculty of cognition and therefore of all knowledge.
Ayn Rand describes materialists as "mystics of muscle" - "mystics" because, like idealists, they reject the faculty of reason. Man, they hold, is essentially a body without a mind. His conclusions, accordingly, reflect not the objective methodology of reason and logic, but the blind operation of physical factors, such as atomic dances in the cerebrum, glandular squirtings, S-R conditioning, or the tools of production moving in that weird, waltzlike contortion known as the dialectic process.
Despite their implicit mysticism, materialists typically declare that their viewpoint constitutes the only scientific or naturalistic approach to philosophy. The belief in consciousness, they explain, implies supernaturalism. This claim represents a capitulation to idealism. For centuries the idealists maintained that the soul is a divine fragment or mystic ingredient longing to escape the "prison of the flesh"; the idealists invented the false alternative of consciousness versusscience. The materialists simply take over this false alternative, then promote the other side of it. This amounts to rejecting arbitrarily the possibility of a naturalistic view of consciousness.
The facts, however, belie any equation of consciousness with mysticism. Consciousness is an attribute of perceived entities here on earth. It is a faculty possessed under definite conditions by a certain group of living organisms. It is directly observable (by introspection). It has a specific nature, including specific physical organs, and acts accordingly, i.e., lawfully. It has a life-sustaining function: to perceive the facts of nature and thereby enable the organisms that possess it to act successfully. In all this, there is nothing unnatural or supernatural. There is no basis for the suggestion that consciousness is separable from matter, let alone opposed to it, no hint of immortality, no kinship to any alleged transcendent realm.
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There is no valid reason to reject consciousness or to struggle to reduce it to matter; not if such reduction means the attempt to define it out of existence. Even if, someday, consciousness were to be explained scientifically as a product of physical conditions, this would not alter any observed fact. It would not alter the fact that, given those conditions, the attributes and functions of consciousness are what they are. ...
-- Leonard Piekoff, Objectivism: The Philosophy of Ayn Rand, 1991