dissenting.
I neither agree that the unanimous decision in Patton v. Bank of LaFayette, 124 Ga. 965, 974 (7) (53 SE 664) (1906) should be overruled nor that the challenged testimony of the Sharpes’ two experts was probative, secondary evidence. For these reasons, I respectfully dissent to the majority’s reversal of the judgment of the Court of Appeals.
The doctrine of “stare decisis” has never been limited to certain *272areas of law. This Court always has been and should continue to be reluctant to overrule its prior unanimous decisions. Slowik v. Knorr, 222 Ga. 669, 671 (151 SE2d 726) (1966). Not long ago, in 1991, this Court reaffirmed Patton v. Bank of LaFayette, supra, and adhered to the long-standing distinction recognized in Georgia between a motion to strike “illegal” evidence and a motion to strike “secondary” evidence: “ ‘A motion to rule out testimony illegally admitted even without objection is never too late until the cause is finally submitted to the jury/ [Cit.]” (Emphasis in original.) Mable v. State, 261 Ga. 379, 381 (1) (405 SE2d 48) (1991). Although Mable was a criminal case, the rationale underlying the distinction applies equally to civil cases and, indeed, was originally set forth in civil cases. See, e.g., Patton v. Bank of LaFayette, supra; Blount v. Beall, 95 Ga. 182, 189 (4) (22 SE 52) (1894); Anderson v. Suggs, 42 Ga. 265 (1871); J. Day & Co. v. Crawford, 13 Ga. 508, 511 (2) (1853). That rationale is that, unlike “secondary” evidence, “illegal” evidence “should not be considered by the jury, and if it is not to be considered by the jury, it should not be admitted for their consideration.” Blount v. Beall, supra at 189 (4). See also Henderson v. State, 162 Ga. App. 320, 328 (292 SE2d 77) (1982) (On Motion For Rehearing); Graham v. Clark, 114 Ga. App. 825, 829 (1) (152 SE2d 789) (1966). A motion to strike “illegal” testimony is especially appropriate in condemnation cases and other cases where complex evidentiary rules and testimony are common. See Dunaway v. Columbia County, 213 Ga. App. 840 (2) (447 SE2d 31) (1994); Dept. of Transp. v. Whitehead, 169 Ga. App. 226, 230 (3) (312 SE2d 344) (1983).
In this case, the Sharpes’ experts assigned a separate value to limestone deposits on the property taken, based on a projected royalty to be paid upon extraction thereof. As a result, they testified to a much higher value of the property than did DOT’s expert. DOT made no contemporaneous objection to the testimony of the Sharpes’ experts, but moved to strike that testimony at the close of the evidence.
A motion to strike illegal testimony is timely if made before the final submission of the case to the jury. Mable v. State, supra at 381 (1); McCalman v. State, 121 Ga. 491, 496-497 (5) (49 SE 609) (1904); Blount v. Beall, supra at 189 (4); Smith v. State, 123 Ga. App. 269, 271 (1) (b) (180 SE2d 556) (1971); Rushin v. State, 63 Ga. App. 646, 647 (1) (11 SE2d 844) (1940). Compare Brown v. Techdata Corp., 238 Ga. 622, 628 (234 SE2d 787) (1977). Thus, if the testimony of the Sharpes’ experts was “illegal” rather than “secondary” evidence, then DOT’s motion to strike was timely, as it was made at the close of evidence and prior to either the closing arguments or the jury charge. See McCalman v. State, supra; Dept. of Transp. v. Whitehead, supra; Rushin v. State, supra. “Secondary” evidence is that which has proba*273tive value and is legal in itself, but which is inadmissible until the proper foundation has been laid. Mable v. State, supra; Patton v. Bank of LaFayette, supra. “Illegal” evidence, on the other hand, either has no probative value, such as hearsay, or its admission is error of constitutional dimension. Mable v. State, supra; Patton v. Bank of LaFayette, supra.
Decided October 7, 1996 Reconsideration denied November 8, 1996. Daniel, Lawson, Tuggle & Jerles, Tom W. Daniel, William R. Jerles, Jr., for appellants. Michael J. Bowers, Attorney General, Cathy A. Cox-Brakefield, Assistant Attorney General, Sell & Melton, John A. Draughon, *274Michelle W. Johnson, for appellee.*273DOT has never asserted that the testimony of the Sharpes’ experts was probative “secondary” evidence which was admitted without the necessary foundation. Rather, DOT urged that the opinions of the Sharpes’ experts improperly utilized the present value of the limestone deposits and, as the Court of Appeals pointed out, this is an assertion that the Sharpes’ experts offered testimony “evidencing the wrong measure of damages” and “altogether without probative force.” Dept. of Transp. v. Sharpe, 219 Ga. App. 466, 467 (1) (465 SE2d 695) (1995). Indeed, if evidence is offered to prove value, based solely on an incorrect measure of damages, then it has no probative value and is, therefore, “illegal” evidence. Ga. Power Co. v. Cannon, 120 Ga. App. 721, 723 (2) (172 SE2d 142) (1969); State Hwy. Dept. v. Mann, 110 Ga. App. 390, 392 (2) (138 SE2d 610) (1964).
As the Court of Appeals and the cases cited by the majority indicate, evidence of the presence of mineral deposits and their effect on the overall value of the property is admissible, but evidence of their separate value is never admissible, in whatever context. Contrary to the majority opinion, the value of the mineral deposits is never relevant in establishing the overall value of the property. Only the presence of the mineral deposits is so relevant. Atlanta Terra Cotta Co. v. Ga. R. &c. Co., 132 Ga. 537, 545-546 (7) (64 SE 563) (1909); Dept. of Transp. v. Sharpe, supra at 468 (2); Williams v. Mayor &c. of Carrollton, 195 Ga. App. 590, 591 (2) (394 SE2d 389) (1990); Southern R. Co. v. Miller, 94 Ga. App. 701, 704 (1) (96 SE2d 297) (1956).
Accordingly, in my opinion, the evidence of the separate value of the mineral deposits was non-probative, “illegal” evidence and, thus, the Court of Appeals correctly held that DOT’s motion to strike was a timely and appropriate means to invoke a ruling on the admissibility of the testimony of the Sharpes’ experts.
I am authorized to state that Justice Hines joins in this dissent.