<PAGE>

                                          
                                   UNITED STATES
                         SECURITIES AND EXCHANGE COMMISSION
                                Washington, DC 20549
                                          
                                          
                                    FORM 10-Q/A

(Mark One)

/X/  QUARTERLY REPORT UNDER SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT
     OF 1934

     For The Quarterly Period Ended July 31, 1998 or

/ /  TRANSITION REPORT UNDER SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT
     OF 1934

     For the transition period from _________________ to _________________

Commission File Number:  1-4488
                                  MESABI TRUST
             (Exact name of registrant as specified in its charter)

                NEW YORK                               13-6022277
     (State or other jurisdiction of      (I.R.S. Employer Identification No.)
     incorporation or organization)

                        IN CARE OF BANKERS TRUST COMPANY,
                         CORPORATE TRUST & AGENCY GROUP
                                  P.O. BOX 318
                              CHURCH STREET STATION
                          NEW YORK, NEW YORK 10008-0318
                    (Address of principal executive offices)

                                 (212) 250-6519
              (Registrant's telephone number, including area code)

Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. Yes  _X_   No  ___

As of September 9, 1998, there were 13,120,010 Units of Beneficial Interest in
Mesabi Trust outstanding.

<PAGE>

ITEM 2.   TRUSTEES' DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
RESULTS OF OPERATIONS.

FORWARD-LOOKING INFORMATION

      Certain statements contained in this document are forward-looking,
including specifically those statements estimating calendar year 1998 production
or shipments.  All such forward-looking statements are based on input from the
lessee/operator.  The Trust has no control over the operations and activities of
the lessee/operator except within the framework of current agreements.  Actual
results could differ materially from those indicated in such statements. 
Important factors that could cause actual results to differ materially include
those listed in "Important Factors Affecting Mesabi Trust" below.

BACKGROUND

      Leasehold royalty income constitutes the principal source of revenue to
Mesabi Trust.  Royalty rates are determined in accordance with the terms of
Mesabi Trust's leases and assignments of leases.  Overriding royalties are
determined by both the volume and selling price of iron ore products shipped. 
Fee royalties payable to Mesabi Land Trust, a Minnesota land trust of which
Mesabi Trust is the sole beneficiary ("Mesabi Land Trust"), are based on the
amount of crude ore mined.  Currently, royalty on crude ore is based on an
agreed price per ton, subject to certain indexing.  Crude ore is used to produce
iron ore pellets and other products.

      Northshore Mining Corporation ("Northshore") is obligated as lessee to pay
Mesabi Trust base overriding royalties in varying amounts.  The volume royalties
constitute a percentage of the gross proceeds of iron ore products produced at
Mesabi Trust lands (and to a limited extent other lands) and shipped from Silver
Bay, Minnesota.  The royalty percentage ranges from 2-1/2% of the gross proceeds
(for the first one million tons of iron ore products so shipped annually) to 6%
of the gross proceeds (for all iron ore products in excess of 4 million tons so
shipped annually).

      With respect to the selling price component of royalty calculation,
Northshore is obligated to pay to Mesabi Trust royalty bonuses.  The royalty
bonus is a percentage of the gross proceeds of product shipped from Silver Bay
and sold at prices above a threshold price.  The threshold price is adjusted on
an annual basis for inflation and deflation (but not below $30).  The threshold
price was $36.62 for calendar year 1996, was $37.29 for calendar year 1997 and
is $38.21 for calendar year 1998.  The royalty bonus percentage ranges from 1/2
of 1% of the gross proceeds (on all tonnage shipped for sale at prices between
the threshold price and $2.00 above the threshold price) to 3% of the gross
proceeds (on all tonnage shipped for sale at prices $10.00 or more above the
threshold price).  No royalty bonus has ever been payable.

      Generally, Northshore's obligation to pay base overriding royalties and
royalty bonuses with respect to the sale of iron ore products accrues upon the
shipment of those products from Silver Bay.   However, Northshore also is
obligated to pay to Mesabi Trust a minimum advance royalty in equal quarterly
installments.  Royalty advances are credited against certain base overriding
royalties and royalty bonuses.  The amount of advance royalties payable is
subject to adjustment for inflation and deflation (but not below $500,000 per
annum).  Advance royalties payable were $610,335 for calendar year 1996, were
$621,606 for calendar year 1997 and are $636,935 for calendar year 1998. 
Northshore is obligated to make quarterly royalty payments in January, April,
July and October of each year.  In the case of base overriding royalties and
royalty bonuses, these quarterly royalty payments are to be made whether or not
the related proceeds of sale have been received by Northshore by the time such
payments become due.

                                         2
<PAGE>

      Due to a combination of factors, shipments from quarter to quarter and
from year to year fluctuate greatly.  These factors include the normal reduction
of Great Lakes shipping activity during the winter months, price fluctuations
and reduced pellet sales resulting from adverse economic conditions affecting
the steel industry generally.

      In its most recently released quarterly report on Form 10-Q for the
quarter ended June 30, 1998, which report was filed on August 12, 1998,
Cleveland-Cliffs, Inc. ("CCI"), parent company of Northshore, the
lessee/operator of Mesabi Trust iron ore interests, stated that it is continuing
to evaluate whether to build a plant at the Northshore Mine to produce pig iron.
The same report stated that CCI has initiated the environmental review and
permitting process and that uncertainties concerning environmental permitting
and other matters have delayed a decision on this project.  CCI's report gave no
indication regarding when a decision would be made with respect to the plant. 
The Mesabi Trustees are unable to determine at this time how the addition of a
pig iron facility (if the project proceeds) would impact overall revenues of
Mesabi Trust.  As indicated elsewhere in this report, the Trust's revenues are
currently derived almost entirely from iron ore pellet production and sales.

      Mesabi Trust has no employees, but it engages independent consultants to
assist the Trustees in monitoring, among other things, the amount and sales
prices of minerals shipped by Northshore from Silver Bay, Minnesota.  As noted
above, the information regarding amounts and sales prices of shipped minerals is
used to compute the royalties payable to Mesabi Trust by Northshore.  Bankers
Trust Company, one of the Trustees, also performs certain administrative
functions for Mesabi Trust.

IMPORTANT FACTORS AFFECTING MESABI TRUST

      The Agreement of Trust governing Mesabi Trust specifically prohibits the
Trustees from entering into or engaging in any business.  This prohibition
applies even to business activities the Trustees deem necessary or proper for
the preservation and protection of the Trust Estate.  Accordingly, the Trustees'
activities in connection with the administration of Trust assets are limited to
collecting income, paying expenses and liabilities, distributing net income and
protecting and conserving the assets held.

      Accordingly, the income of the Trust is highly dependent upon the
activities and operations of Northshore, and the terms and conditions of its
leases and assignments of leases.  The Trust and the Trustees have no control
over the operations and activities of Northshore, except within the framework of
these leases and assignment of leases.

      Due to winter weather, and the increasing royalty percentages based on
tonnage shipped in a calendar year, results for a particular calendar quarter
are typically not indicative of results for future quarters or the year as a
whole.  Factors which can impact the results of the Trust in any quarter or year
include the following:

1.   SHIPPING CONDITIONS IN THE GREAT LAKES.  Shipping activity by Northshore is
     dependent upon when the Great Lakes shipping lanes freeze for the winter
     months (typically in January) and when they re-open in the spring
     (typically late-March or April).  Base overriding royalties to Mesabi Trust
     are based on shipments made in a calendar quarter.  Because there typically
     is little or no shipping activity in the first calendar quarter, the Trust
     typically receives only the minimum royalty for that period.

2.   OPERATIONS OF NORTHSHORE.  Because the primary portion of the Trust's
     revenues derive from iron ore product shipped by Northshore from Silver
     Bay, Northshore's processing and shipping activities directly impact the
     Trust's revenues in each quarter and for each year.  In turn, a myriad 

                                         3

<PAGE>

     of factors affect Northshore shipment volume.  These factors 
     include economic conditions in the iron ore industry, pricing by 
     competitors, long-term customer contracts or arrangements by 
     Northshore or its competitors, availability of ore boats, 
     production at Northshore's mining operations, and production at the 
     pelletizing/processing facility.  If any pelletizing line becomes 
     idle for any reason, production and shipments (and, consequently, 
     Trust income) could be adversely impacted.
     
3.   INCREASING ROYALTIES.  As described elsewhere in this Report, the royalty
     percentage paid to the Trust increases as the aggregate tonnage of iron ore
     products shipped, attributable to the Trust, in any calendar year
     increases.  Assuming a consistent sales price per ton throughout a calendar
     year, shipments of iron ore product attributable to the Trust later in the
     year generate a higher royalty to the Trust.  

4.   PERCENTAGE OF MESABI TRUST ORE.  As described elsewhere in this Report,
     Northshore has the ability to process and ship iron ore product from lands
     other than Mesabi Trust lands. In certain circumstances, the Trust may be
     entitled to royalties on those other shipments, but not in all cases.  In
     general, the Trust will receive higher royalties (assuming all other
     factors are equal) if a higher percentage of shipments are from Mesabi
     Trust lands.  The percentages of shipments that came from Mesabi Trust
     lands were 98.3%, 98.4%, 90.6% and 88.3% in calendar years 1997, 1996, 1995
     and 1994, respectively.

COMPARISON OF THREE MONTHS ENDED JULY 31, 1998 AND JULY 31, 1997

      Mesabi Trust's net income increased to $1,384,068 for the fiscal quarter
ended July 31, 1998, as compared to net income of $1,178,741 for the fiscal
quarter ended July 31, 1997.  Mesabi Trust's gross income for the fiscal quarter
ended July 31, 1998 was $1,481,240, consisting of $424,861 in minimum advance
royalty income, $960,296 in overriding royalty income, $87,865 in fee royalty
income and $8,218 in interest income, as compared to gross income of $1,259,552
consisting of $414,326 in minimum advance royalty income, $768,115 in overriding
royalty income, $71,078 in fee royalty income and $6,033 in interest income, for
the fiscal quarter ended July 31, 1997.  The increase in royalty income was
primarily due to increased pellet shipments as compared to the comparable prior
period.  Mesabi Trust's expenses for the fiscal quarter ended July 31, 1998 were
$97,172, compared to expenses of $80,811 for the fiscal quarter ended July 31,
1997.

COMPARISON OF SIX MONTHS ENDED JULY 31, 1998 AND JULY 31, 1997

      Mesabi Trust's gross income for the six months ended July 31, 1998 was
$1,980,691, an increase of $471,394 from the gross income of $1,509,297 for the
six months ended July 31, 1997.  The increase in royalty income was primarily
due to increased pellet shipments and increased crude ore production (increasing
the amount of fee royalty income).  Interest income was slightly higher in the
1998 period.  Expenses of $166,889 for the six months ended July 31, 1998
increased $20,380 from expenses of $146,509 for the six months ended July 31,
1997.  The increased income and increased expenses resulted in net income of
$1,813,802 for the six months ended July 31, 1998 as compared to net income of
$1,362,788 for the six months ended July 31, 1997.

      Mesabi Trust's Unallocated Reserve aggregated $1,090,400 at July 31, 1998,
as compared with an Unallocated Reserve of $1,160,595 at July 31, 1997.  The
decrease of $70,195 was due to the net effect of: (a) the increase in net income
of $451,014 during the six months ended July 31, 1998 as compared with the six
months ended July 31, 1997 and (b) the January 31, 1998 unallocated reserve
balance of $719,799 was $69,191 higher than the January 31, 1997 unallocated
reserve balance of $650,608.  The Trustees anticipate that the amount of
Unallocated Reserve will fluctuate from time to 

                                         4

<PAGE>

time, depending upon a number of factors, including but not limited to the 
income for a particular period, the amount and timing of distributions, 
uncertainty about future royalty income and the uncertainty of future 
expenses.










                                         5

<PAGE>


                                     SIGNATURES

                Pursuant to the requirements of the Securities Exchange Act of 
1934, the registrant has duly caused this Amendment to be signed on its behalf 
by the undersigned thereunto duly authorized.


                                                MESABI TRUST
                            ---------------------------------------------
                                                (Registrant)

                            By: BANKERS TRUST COMPANY
                            Corporate Trustee
                            Principal Administrative Officer and duly authorized
                            signatory:*


Date: November 12, 1998    By:       /s/ Robert Caporale
                              --------------------------------------------
                                      Name:  Robert Caporale
                                      Title:    Vice President


* There are no directors
  or executive officers of 
  the registrant.


                                      6